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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 default_index(func):
 """Decorator assuring the wrapped method may only run if we are the default repository index. This is as we rely on git commands that operate on that index only. """


    @wraps(func)
    def check_default_index(self, *args, **kwargs):
        if self._file_path != self._index_path():
            raise AssertionError(
                "Cannot call %r on indices that do not represent the default git index" % func.__name__)
        return func(self, *args, **kwargs)
    # END wrapper method

    return check_default_index