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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 stream(self, f, blank_solutions=False, include_unspents=False, include_witness_data=True):
 """Stream a Bitcoin transaction Tx to the file-like object f. :param f: writable file-like object to stream binary data of transaction :param blank_solutions: (optional) clear out the solutions scripts, effectively "unsigning" the transaction before writing it. Defaults to False :param include_unspents: (optional) stread out the Spendable objects after streaming the transaction. This is a pycoin-specific extension. Defaults to False. :param include_witness_data: (optional) stream segwit transactions including the witness data if the transaction has any witness data. Defaults to True. """

        include_witnesses = include_witness_data and self.has_witness_data()
        stream_struct("L", f, self.version)
        if include_witnesses:
            f.write(b'\0\1')
        stream_struct("I", f, len(self.txs_in))
        for t in self.txs_in:
            t.stream(f, blank_solutions=blank_solutions)
        stream_struct("I", f, len(self.txs_out))
        for t in self.txs_out:
            t.stream(f)
        if include_witnesses:
            for tx_in in self.txs_in:
                witness = tx_in.witness
                stream_struct("I", f, len(witness))
                for w in witness:
                    stream_satoshi_string(f, w)
        stream_struct("L", f, self.lock_time)
        if include_unspents and not self.missing_unspents():
            self.stream_unspents(f)