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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 _Completion(self, match):
 # pylint: disable=C6114 r"""Replaces double square brackets with variable length completion. Completion cannot be mixed with regexp matching or '\' characters i.e. '[[(\n)]] would become (\(n)?)?.' Args: match: A regex Match() object. Returns: String of the format '(a(b(c(d)?)?)?)?'. """

    # Strip the outer '[[' & ']]' and replace with ()? regexp pattern.
    word = str(match.group())[2:-2]
    return '(' + ('(').join(word) + ')?' * len(word)