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--- work:2024-49 [2024/12/14 01:31] – [Pesquisa] magsilva
+++ work:2024-49 [2024/12/14 01:49] (current) – magsilva
@@ Line 8: / Line 8: @@
 ===== Pesquisa =====
   * Correção automática de programas
-    * Um problema que tive recentemente foi quanto a redefinição de módulos e funções da biblioteca básica do Python.
+    * Um problema que tive recentemente foi quanto a redefinição de módulos (e suas funções) da biblioteca básica do Python. As funções que estão no módulo ''builtins'' é simples redefinir (basta definir a função manualmente, no escopo global), mas um módulo é importado durante a execução do programa (e qualquer definição no escopo global anterior seria sobreescrita).
     * Normalmente, poderíamos usar dublês (mocks) para sobrepor o comportamento de alguma função ou método de uma classe. No entanto, isso não é tecnicamente possível (ao menos com as ferramentas atuais) para os módulos e funções da biblioteca básica/padrão do Python (builtin).
     * Mais especificamente, eu precisava sobreescrever o comportamento da função ''time'' do módulo ''time''.
@@ Line 21: / Line 21: @@
       * As classes a serem utilizadas estão definidas na variável ''sys.meta_path''. Basicamente, ao procurar por um nome (módulo, função ou variável), o Python percorre os objetos disponíveis nessa variável, utilizando-os para encontrar o que deseja.
     * Entendido isso, bastaria criar uma nova classe Finder e colocá-la no início do caminho.
-    * No entanto, no código de importação do módulo ''importlib'' é feito um grande esforço para não permitir a sobreescrita de módulos builtins. Na função ''_find_and_load()' do '_bootstrap.py', antes de começar a busca pelo módulo é verificado se ele está presente em ''sys.modules''. Em
+    * Bom, nem tudo são flores. Por algum motivo muito estranho, **alguns** módulos builtins do Python não podem ser sobreescritos por esse mecanismo. Mais especificamente o módulo ''time'' não pode. No código de importação do módulo ''importlib'' é feito um grande esforço para não permitir a sobreescrita de módulos builtins. Na função ''_find_and_load()'' do ''_bootstrap.py'', antes de começar a busca pelo módulo é verificado se ele está presente em ''sys.modules'' (um dicionário de nome de módulo para o módulo em si). Por exemplo, hoje, em minha máquina, tenho os seguintes módulos nessa variável (e olha o ''time'' lá no fim!): _abc, abc, abrt_exception_handler3, _ast, ast, atexit, builtins, _codecs, codecs, _collections, collections, _collections_abc, collections.abc, contextlib, copyreg, _datetime, datetime, dis, _distutils_hack, encodings, encodings.aliases, encodings.utf_8, encodings.utf_8_sig, enum, errno, _frozen_importlib, _frozen_importlib_external, _functools, functools, __future__, genericpath, google, _imp, importlib, importlib._abc, importlib._bootstrap, importlib._bootstrap_external, importlib.machinery, importlib.util, inspect, _io, io, itertools, keyword, linecache, logging, __main__, marshal, _opcode, opcode, _operator, operator, os, os.path, paste, platform, posix, posixpath, re, readline, re._casefix, re._compiler, re._constants, re._parser, reprlib, rlcompleter, _signal, site, _sitebuiltins, _sre, _stat, stat, _string, string, sys, syslog, systemd, systemd.id128, systemd._journal, systemd.journal, systemd._reader, textwrap, _thread, threading, **time**, token, _tokenize, tokenize, traceback, types, _uuid, uuid, _warnings, warnings, _weakref, weakref, _weakrefset, zipimport.
+    * Minha primeira abordagem foi alterar o código da importação para que não ocorresse mais esse impedimento de sobreescrever elementos builtins. Isso funcionou! Colocarei o código a seguir, que sobreescreve o ''time.time()''. O código compreende a criação de duas classes, ''MissingNameFinder'' e ''MissingLoader'', responsáveis por procurar o nome e, ao não encontrá-lo, usar o ''MissingLoader'' para criar, em tempo de execução, o módulo (classe ''LazyModule''), constante ou função (classe ''LazyFunction''). O que sobrou é código aproveitado do ''importlib'':
+<code language="python">
+from typing import Any, Callable, Dict, List, Optional
+import importlib
+import sys
+import importlib.abc
+import _imp
-    * Bom, nem tudo são flores. Por algum motivo muito estranho, **alguns** módulos builtins do Python não podem ser sobreescritos por esse mecanismo. Mais especificamente o módulo ''time'' não pode.
+def _verbose_message(message, *args, verbosity=1):
+    """Print the message to stderr if -v/PYTHONVERBOSE is turned on."""
+    if sys.flags.verbose >= verbosity:
+        if not message.startswith(('#', 'import ')):
+            message = '# ' + message
+        print(message.format(*args), file=sys.stderr)
+def _find_spec(name, path, target=None):
+    """Find a module's spec."""
+    meta_path = sys.meta_path
+    if meta_path is None:
+        # PyImport_Cleanup() is running or has been called.
+        raise ImportError("sys.meta_path is None, Python is likely shutting down")
+    if not meta_path:
+        _warnings.warn('sys.meta_path is empty', ImportWarning)
+    # We check sys.modules here for the reload case.  While a passed-in
+    # target will usually indicate a reload there is no guarantee, whereas
+    # sys.modules provides one.
+    is_reload = name in sys.modules
+    for finder in meta_path:
+        try:
+            find_spec = finder.find_spec
+        except AttributeError:
+           continue
+        else:
+            spec = find_spec(name, path, target)
+        if spec is not None:
+            # The parent import may have already imported this module.
+            if not is_reload and name in sys.modules:
+                module = sys.modules[name]
+                try:
+                    __spec__ = module.__spec__
+                except AttributeError:
+                    # We use the found spec since that is the one that
+                    # we would have used if the parent module hadn't
+                    # beaten us to the punch.
+                    return spec
+                else:
+                    if __spec__ is None:
+                        return spec
+                    else:
+                        return __spec__
+            else:
+                return spec
+    else:
+        return None
+def _sanity_check(name, package, level):
+    """Verify arguments are "sane"."""
+    if not isinstance(name, str):
+        raise TypeError(f'module name must be str, not {type(name)}')
+    if level < 0:
+        raise ValueError('level must be >= 0')
+    if level > 0:
+        if not isinstance(package, str):
+            raise TypeError('__package__ not set to a string')
+        elif not package:
+            raise ImportError('attempted relative import with no known parent package')
+    if not name and level == 0:
+        raise ValueError('Empty module name')
+def _resolve_name(name, package, level):
+    """Resolve a relative module name to an absolute one."""
+    bits = package.rsplit('.', level - 1)
+    if len(bits) < level:
+        raise ImportError('attempted relative import beyond top-level package')
+    base = bits[0]
+    return f'{base}.{name}' if name else base
+def _init_module_attrs(spec, module, *, override=False):
+    # The passed-in module may be not support attribute assignment,
+    # in which case we simply don't set the attributes.
+    # __name__
+    if (override or getattr(module, '__name__', None) is None):
+        try:
+            module.__name__ = spec.name
+        except AttributeError:
+            pass
+    # __loader__
+    if override or getattr(module, '__loader__', None) is None:
+        loader = spec.loader
+        if loader is None:
+            # A backward compatibility hack.
+            if spec.submodule_search_locations is not None:
+                if _bootstrap_external is None:
+                    raise NotImplementedError
+                NamespaceLoader = _bootstrap_external.NamespaceLoader
+                loader = NamespaceLoader.__new__(NamespaceLoader)
+                loader._path = spec.submodule_search_locations
+                spec.loader = loader
+                # While the docs say that module.__file__ is not set for
+                # built-in modules, and the code below will avoid setting it if
+                # spec.has_location is false, this is incorrect for namespace
+                # packages.  Namespace packages have no location, but their
+                # __spec__.origin is None, and thus their module.__file__
+                # should also be None for consistency.  While a bit of a hack,
+                # this is the best place to ensure this consistency.
+                #
+                # See # https://docs.python.org/3/library/importlib.html#importlib.abc.Loader.load_module
+                # and bpo-32305
+                module.__file__ = None
+        try:
+            module.__loader__ = loader
+        except AttributeError:
+            pass
+    # __package__
+    if override or getattr(module, '__package__', None) is None:
+        try:
+            module.__package__ = spec.parent
+        except AttributeError:
+            pass
+    # __spec__
+    try:
+        module.__spec__ = spec
+    except AttributeError:
+        pass
+    # __path__
+    if override or getattr(module, '__path__', None) is None:
+        if spec.submodule_search_locations is not None:
+            # XXX We should extend __path__ if it's already a list.
+            try:
+                module.__path__ = spec.submodule_search_locations
+            except AttributeError:
+                pass
+    # __file__/__cached__
+    if spec.has_location:
+        if override or getattr(module, '__file__', None) is None:
+            try:
+                module.__file__ = spec.origin
+            except AttributeError:
+                pass
+        if override or getattr(module, '__cached__', None) is None:
+            if spec.cached is not None:
+                try:
+                    module.__cached__ = spec.cached
+                except AttributeError:
+                    pass
+    return module
+def module_from_spec(spec):
+    """Create a module based on the provided spec."""
+    # Typically loaders will not implement create_module().
+    module = None
+    if hasattr(spec.loader, 'create_module'):
+        # If create_module() returns `None` then it means default
+        # module creation should be used.
+        module = spec.loader.create_module(spec)
+    elif hasattr(spec.loader, 'exec_module'):
+        raise ImportError('loaders that define exec_module() '
+                          'must also define create_module()')
+    if module is None:
+        module = _new_module(spec.name)
+    _init_module_attrs(spec, module)
+    return module
+def _load_unlocked(spec):
+    # A helper for direct use by the import system.
+    if spec.loader is not None:
+        # Not a namespace package.
+        if not hasattr(spec.loader, 'exec_module'):
+            msg = (f"{_object_name(spec.loader)}.exec_module() not found; "
+                    "falling back to load_module()")
+            _warnings.warn(msg, ImportWarning)
+            return _load_backward_compatible(spec)
+    module = module_from_spec(spec)
+    # This must be done before putting the module in sys.modules
+    # (otherwise an optimization shortcut in import.c becomes
+    # wrong).
+    spec._initializing = True
+    try:
+        sys.modules[spec.name] = module
+        try:
+            if spec.loader is None:
+                if spec.submodule_search_locations is None:
+                    raise ImportError('missing loader', name=spec.name)
+                # A namespace package so do nothing.
+            else:
+                spec.loader.exec_module(module)
+        except:
+            try:
+                del sys.modules[spec.name]
+            except KeyError:
+                pass
+            raise
+        # Move the module to the end of sys.modules.
+        # We don't ensure that the import-related module attributes get
+        # set in the sys.modules replacement case.  Such modules are on
+        # their own.
+        module = sys.modules.pop(spec.name)
+        sys.modules[spec.name] = module
+        _verbose_message('import {!r} # {!r}', spec.name, spec.loader)
+    finally:
+        spec._initializing = False
+    return module
+def _find_and_load_unlocked(name, import_):
+    path = None
+    parent = name.rpartition('.')[0]
+    parent_spec = None
+    if parent:
+        if parent not in sys.modules:
+            _call_with_frames_removed(import_, parent)
+        # Crazy side-effects!
+        if name in sys.modules:
+            return sys.modules[name]
+        parent_module = sys.modules[parent]
+        try:
+            path = parent_module.__path__
+        except AttributeError:
+            msg = f'{_ERR_MSG_PREFIX}{name!r}; {parent!r} is not a package'
+            raise ModuleNotFoundError(msg, name=name) from None
+        parent_spec = parent_module.__spec__
+        child = name.rpartition('.')[2]
+    spec = _find_spec(name, path)
+    if spec is None:
+        raise ModuleNotFoundError(f'{_ERR_MSG_PREFIX}{name!r}', name=name)
+    else:
+        if parent_spec:
+            # Temporarily add child we are currently importing to parent's
+            # _uninitialized_submodules for circular import tracking.
+            parent_spec._uninitialized_submodules.append(child)
+        try:
+            module = _load_unlocked(spec)
+        finally:
+            if parent_spec:
+                parent_spec._uninitialized_submodules.pop()
+    if parent:
+        # Set the module as an attribute on its parent.
+        parent_module = sys.modules[parent]
+        try:
+            setattr(parent_module, child, module)
+        except AttributeError:
+            msg = f"Cannot set an attribute on {parent!r} for child module {child!r}"
+            _warnings.warn(msg, ImportWarning)
+    return module
+def _find_and_load(name, import_):
+    """Find and load the module."""
+    # Optimization: we avoid unneeded module locking if the module
+    # already exists in sys.modules and is fully initialized.
+    # module = sys.modules.get(name, _NEEDS_LOADING)
+    return _find_and_load_unlocked(name, import_)
+    if module is None:
+        message = f'import of {name} halted; None in sys.modules'
+        raise ModuleNotFoundError(message, name=name)
+    return module
+def _gcd_import(name, package=None, level=0):
+    """Import and return the module based on its name, the package the call is
+    being made from, and the level adjustment.
+    This function represents the greatest common denominator of functionality
+    between import_module and __import__. This includes setting __package__ if
+    the loader did not.
+    """
+    _sanity_check(name, package, level)
+    if level > 0:
+        name = _resolve_name(name, package, level)
+    return _find_and_load(name, _gcd_import)
+def __import__(name, globals=None, locals=None, fromlist=(), level=0):
+    """Import a module.
+    The 'globals' argument is used to infer where the import is occurring from
+    to handle relative imports. The 'locals' argument is ignored. The
+    'fromlist' argument specifies what should exist as attributes on the module
+    being imported (e.g. ``from module import <fromlist>``).  The 'level'
+    argument represents the package location to import from in a relative
+    import (e.g. ``from ..pkg import mod`` would have a 'level' of 2).
+    """
+    if level == 0:
+        module = _gcd_import(name)
+    else:
+        globals_ = globals if globals is not None else {}
+        package = _calc___package__(globals_)
+        module = _gcd_import(name, package, level)
+    if not fromlist:
+        # Return up to the first dot in 'name'. This is complicated by the fact
+        # that 'name' may be relative.
+        if level == 0:
+            return _gcd_import(name.partition('.')[0])
+        elif not name:
+            return module
+        else:
+            # Figure out where to slice the module's name up to the first dot
+            # in 'name'.
+            cut_off = len(name) - len(name.partition('.')[0])
+            # Slice end needs to be positive to alleviate need to special-case
+            # when ``'.' not in name``.
+            return sys.modules[module.__name__[:len(module.__name__)-cut_off]]
+    elif hasattr(module, '__path__'):
+        return _handle_fromlist(module, fromlist, _gcd_import)
+    else:
+        return module
+class ModuleSpec:
+    """The specification for a module, used for loading.
+    A module's spec is the source for information about the module.  For
+    data associated with the module, including source, use the spec's
+    loader.
+    `name` is the absolute name of the module.  `loader` is the loader
+    to use when loading the module.  `parent` is the name of the
+    package the module is in.  The parent is derived from the name.
+    `is_package` determines if the module is considered a package or
+    not.  On modules this is reflected by the `__path__` attribute.
+    `origin` is the specific location used by the loader from which to
+    load the module, if that information is available.  When filename is
+    set, origin will match.
+    `has_location` indicates that a spec's "origin" reflects a location.
+    When this is True, `__file__` attribute of the module is set.
+    `cached` is the location of the cached bytecode file, if any.  It
+    corresponds to the `__cached__` attribute.
+    `submodule_search_locations` is the sequence of path entries to
+    search when importing submodules.  If set, is_package should be
+    True--and False otherwise.
+    Packages are simply modules that (may) have submodules.  If a spec
+    has a non-None value in `submodule_search_locations`, the import
+    system will consider modules loaded from the spec as packages.
+    Only finders (see importlib.abc.MetaPathFinder and
+    importlib.abc.PathEntryFinder) should modify ModuleSpec instances.
+    """
+    def __init__(self, name, loader, *, origin=None, loader_state=None,
+                 is_package=None):
+        self.name = name
+        self.loader = loader
+        self.origin = origin
+        self.loader_state = loader_state
+        self.submodule_search_locations = [] if is_package else None
+        self._uninitialized_submodules = []
+        # file-location attributes
+        self._set_fileattr = False
+        self._cached = None
+    def __repr__(self):
+        args = [f'name={self.name!r}', f'loader={self.loader!r}']
+        if self.origin is not None:
+            args.append(f'origin={self.origin!r}')
+        if self.submodule_search_locations is not None:
+            args.append(f'submodule_search_locations={self.submodule_search_locations}')
+        return f'{self.__class__.__name__}({", ".join(args)})'
+    def __eq__(self, other):
+        smsl = self.submodule_search_locations
+        try:
+            return (self.name == other.name and
+                    self.loader == other.loader and
+                    self.origin == other.origin and
+                    smsl == other.submodule_search_locations and
+                    self.cached == other.cached and
+                    self.has_location == other.has_location)
+        except AttributeError:
+            return NotImplemented
+    @property
+    def cached(self):
+        if self._cached is None:
+            if self.origin is not None and self._set_fileattr:
+                if _bootstrap_external is None:
+                    raise NotImplementedError
+                self._cached = _bootstrap_external._get_cached(self.origin)
+        return self._cached
+    @cached.setter
+    def cached(self, cached):
+        self._cached = cached
+    @property
+    def parent(self):
+        """The name of the module's parent."""
+        if self.submodule_search_locations is None:
+            return self.name.rpartition('.')[0]
+        else:
+            return self.name
+    @property
+    def has_location(self):
+        return self._set_fileattr
+    @has_location.setter
+    def has_location(self, value):
+        self._set_fileattr = bool(value)
+def spec_from_loader(name, loader, *, origin=None, is_package=None):
+    """Return a module spec based on various loader methods."""
+    if origin is None:
+        origin = getattr(loader, '_ORIGIN', None)
+    if not origin and hasattr(loader, 'get_filename'):
+        if _bootstrap_external is None:
+            raise NotImplementedError
+        spec_from_file_location = _bootstrap_external.spec_from_file_location
+        if is_package is None:
+            return spec_from_file_location(name, loader=loader)
+        search = [] if is_package else None
+        return spec_from_file_location(name, loader=loader,
+                                       submodule_search_locations=search)
+    if is_package is None:
+        if hasattr(loader, 'is_package'):
+            try:
+                is_package = loader.is_package(name)
+            except ImportError:
+                is_package = None  # aka, undefined
+        else:
+            # the default
+            is_package = False
+    return ModuleSpec(name, loader, origin=origin, is_package=is_package)
+def _spec_from_module(module, loader=None, origin=None):
+    # This function is meant for use in _setup().
+    try:
+        spec = module.__spec__
+    except AttributeError:
+        pass
+    else:
+        if spec is not None:
+            return spec
+    name = module.__name__
+    if loader is None:
+        try:
+            loader = module.__loader__
+        except AttributeError:
+            # loader will stay None.
+            pass
+    try:
+        location = module.__file__
+    except AttributeError:
+        location = None
+    if origin is None:
+        if loader is not None:
+            origin = getattr(loader, '_ORIGIN', None)
+        if not origin and location is not None:
+            origin = location
+    try:
+        cached = module.__cached__
+    except AttributeError:
+        cached = None
+    try:
+        submodule_search_locations = list(module.__path__)
+    except AttributeError:
+        submodule_search_locations = None
+    spec = ModuleSpec(name, loader, origin=origin)
+    spec._set_fileattr = False if location is None else (origin == location)
+    spec.cached = cached
+    spec.submodule_search_locations = submodule_search_locations
+    return spec
+class MissingNameFinder(importlib.abc.MetaPathFinder):
+    def __init__(self) -> None:
+        self.forbidden_modules = []
+        self.builtin_modules = sys.builtin_module_names
+        self.allowed_builtin_modules_override = ["time"]
+        self.loader = MissingLoader()
+    def _spec_from_loader(self, name, loader, *, origin=None, is_package=None):
+        """Return a module spec based on various loader methods."""
+        if origin is None:
+            origin = getattr(loader, '_ORIGIN', None)
+        if not origin and hasattr(loader, 'get_filename'):
+            if _bootstrap_external is None:
+                raise NotImplementedError
+            spec_from_file_location = _bootstrap_external.spec_from_file_location
+            if is_package is None:
+                return spec_from_file_location(name, loader=loader)
+            search = [] if is_package else None
+            return spec_from_file_location(name, loader=loader, submodule_search_locations=search)
+        if is_package is None:
+            if hasattr(loader, 'is_package'):
+                try:
+                    is_package = loader.is_package(name)
+                except ImportError:
+                    is_package = None  # aka, undefined
+            else:
+                # the default
+                is_package = False
+        return ModuleSpec(name, loader, origin=origin, is_package=is_package)
+    def find_spec(self, fullname, path, target = None):
+        if fullname == "time" or fullname == "time30":
+            return self._spec_from_loader(fullname, self.loader)
+        else:
+            return None
+        if path:
+            return None
+        if '.' in fullname or fullname in self.forbidden_modules:
+            return None
+        if fullname in self.builtin_modules:
+            if fullname in self.allowed_builtin_modules_override:
+                return importlib.util.spec_from_loader(fullname, self.loader)
+            else:
+                return None
+        return self._spec_from_loader(fullname, self.loader)
+class MissingLoader():
+    def __init__(self) -> None:
+        pass
+    def create_module(self, spec):
+        return LazyModule(spec.name)
+    def exec_module(self, _module):
+        pass
+class LazyModule():
+    def __init__(self, name: str) -> None:
+        self.name = name
+        self._values: Dict[str, Any] = {}
+        self._existing_lines: List[str] = []
+    def __getattr__(self, name: str) -> Any:
+        existing = self._values.get(name, None)
+        if existing:
+            return existing
+        if name.upper() == name:
+            value = 1731593707.2131279
+            value = self._generate_constant(value, value)
+        else:
+            value = """def time():
+    return 1731593707.2131279"""
+            value = self._generate_function(name, value)
+        return value
+    def _generate_constant(self, constant_name: str, constant_value: Any) -> Any:
+        self._values[constant_name] = constant_value
+        self.add_code("%s = %s" % (constante_name, constant_string))
+        return constant_value
+    def _generate_function(self, function_name: str, function_code: str) -> Callable:
+        return LazyFunction(function_name, function_code, self)
+    @property
+    def code(self):
+        return '\n'.join(self._existing_lines)
+    def add_code(self, code: str):
+        exec(code, self._values)
+        self._existing_lines.extend(code.splitlines())
+        self._existing_lines.append('')
+    def get_value(self, name: str) -> Any:
+        return self._values[name]
+class LazyFunction:
+    def __init__(self, name: str, code: str, parent_module: LazyModule) -> None:
+        self.name = name
+        self.code = code
+        self._parent_module = parent_module
+        self._generated_function: Optional[Callable] = None
+    def __call__(self, *args, **kwargs) -> Any:
+        if self._generated_function:
+            return self._generated_function(*args, **kwargs)
+        self._parent_module.add_code(self.code)
+        self._generated_function = self._parent_module.get_value(self.name)
+        return self._generated_function(*args, **kwargs)
+    def __iter__(self):
+        return self
+    def __next__(self):
+        raise StopIteration
+# name_finder = MissingNameFinder()
+# sys.meta_path.insert(0, name_finder)
+# time = __import__("time")
+</code>
+    * Minha segunda abordagem foi perceber que eu poderia apagar o módulo ''time'' da variável ''sys.modules''. Com isso eu tenho um código bem mais enxuto:
+<code language="Python">
+from typing import Any, Callable, Dict, List, Optional
+import importlib
+import sys
+import importlib.abc
+class MissingNameFinder(importlib.abc.MetaPathFinder):
+    def __init__(self) -> None:
+        self.forbidden_modules = []
+        self.builtin_modules = sys.builtin_module_names
+        self.allowed_builtin_modules_override = ["time"]
+        self.loader = MissingLoader()
+    def find_spec(self, fullname, path, target = None):
+        if fullname == "time" or fullname == "time30":
+            return importlib.util.spec_from_loader(fullname, self.loader)
+        else:
+            return None
+        if path:
+            return None
+        if '.' in fullname or fullname in self.forbidden_modules:
+            return None
+        if fullname in self.builtin_modules:
+            if fullname in self.allowed_builtin_modules_override:
+                return importlib.util.spec_from_loader(fullname, self.loader)
+            else:
+                return None
+        return importlib.util.spec_from_loader(fullname, self.loader)
+class MissingLoader():
+    def __init__(self) -> None:
+        pass
+    def create_module(self, spec):
+        return LazyModule(spec.name)
+    def exec_module(self, _module):
+        pass
+class LazyModule():
+    def __init__(self, name: str) -> None:
+        self.name = name
+        self._values: Dict[str, Any] = {}
+        self._existing_lines: List[str] = []
+    def __getattr__(self, name: str) -> Any:
+        existing = self._values.get(name, None)
+        if existing:
+            return existing
+        if name.upper() == name:
+            value = 1731593707.2131279
+            value = self._generate_constant(value, value)
+        else:
+            value = """def time():
+    return 1731593707.2131279"""
+            value = self._generate_function(name, value)
+        return value
+    def _generate_constant(self, constant_name: str, constant_value: Any) -> Any:
+        self._values[constant_name] = constant_value
+        self.add_code("%s = %s" % (constante_name, constant_string))
+        return constant_value
+    def _generate_function(self, function_name: str, function_code: str) -> Callable:
+        return LazyFunction(function_name, function_code, self)
+    @property
+    def code(self):
+        return '\n'.join(self._existing_lines)
+    def add_code(self, code: str):
+        exec(code, self._values)
+        self._existing_lines.extend(code.splitlines())
+        self._existing_lines.append('')
+    def get_value(self, name: str) -> Any:
+        return self._values[name]
+class LazyFunction:
+    def __init__(self, name: str, code: str, parent_module: LazyModule) -> None:
+        self.name = name
+        self.code = code
+        self._parent_module = parent_module
+        self._generated_function: Optional[Callable] = None
+    def __call__(self, *args, **kwargs) -> Any:
+        if self._generated_function:
+            return self._generated_function(*args, **kwargs)
+        self._parent_module.add_code(self.code)
+        self._generated_function = self._parent_module.get_value(self.name)
+        return self._generated_function(*args, **kwargs)
+    def __iter__(self):
+        return self
+    def __next__(self):
+        raise StopIteration
+name_finder = MissingNameFinder()
+sys.meta_path.insert(0, name_finder)
+del(sys.modules["time"])
+time = __import__("time"!
+print(1731593707.2131279)
+print(time.time())
+</code>
+    * Bom, em condições normais isso deveria funcionar. Agora já tenho um bom mecanismo para sobreescrever os módulos e suas funções em tempo de execução!