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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def Find(self, find_specs=None):
 """Searches for matching file entries within the file system. Args: find_specs (list[FindSpec]):
 find specifications. where None will return all allocated file entries. Yields: PathSpec: path specification of a matching file entry. """

    if not find_specs:
      find_specs.append(FindSpec())

    for find_spec in find_specs:
      find_spec.PrepareMatches(self._file_system)

    if path_spec_factory.Factory.IsSystemLevelTypeIndicator(
        self._file_system.type_indicator):
      file_entry = self._file_system.GetFileEntryByPathSpec(self._mount_point)
    else:
      file_entry = self._file_system.GetRootFileEntry()

    for matching_path_spec in self._FindInFileEntry(file_entry, find_specs, 0):
      yield matching_path_spec