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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 get_repo(self, cached=True):
 """Get a git repository object for this instance."""

        module = sys.modules[self.__module__]
        # We use module.__file__ instead of module.__path__[0]
        # to include modules without a __path__ attribute.
        if hasattr(self.__class__, '_repo') and cached:
            repo = self.__class__._repo
        elif hasattr(module, '__file__'):
            path = os.path.realpath(module.__file__)
            try:
                repo = git.Repo(path, search_parent_directories=True)
            except InvalidGitRepositoryError:
                repo = None
        else:
            repo = None
        self.__class__._repo = repo
        return repo