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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 len(self):
 """Length of the data stream"""

        # The len property is needed for requests.
        # requests checks __len__, then len
        # Since we cannot implement __len__ because python 32-bit uses 32-bit
        # sizes, we implement this instead.
        def stream_len(stream):
            """Stream length"""
            cur = stream.tell()
            try:
                stream.seek(0, 2)
                return stream.tell() - cur
            finally:
                stream.seek(cur)

        return sum(stream_len(s) for s in self.streams)