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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 _path_completer_grammar(self):
 """ Return the grammar for matching paths inside strings inside Python code. """

        # We make this lazy, because it delays startup time a little bit.
        # This way, the grammar is build during the first completion.
        if self._path_completer_grammar_cache is None:
            self._path_completer_grammar_cache = self._create_path_completer_grammar()
        return self._path_completer_grammar_cache