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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 __decode_webpush_b64(self, data):
 """ Re-pads and decodes urlsafe base64. """

        missing_padding = len(data) % 4
        if missing_padding != 0:
            data += '=' * (4 - missing_padding)
        return base64.urlsafe_b64decode(data)