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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_input_data(self, request):
 """ If there is data, parse it, otherwise return None. """

        # only PUT and POST should provide data
        if not self._is_data_method(request):
            return None

        content = [row for row in request.read()]
        content = ''.join(content) if content else None
        return self._parse_input_data(content, request) if content else None