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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 begin(self):
 """ This method will implement the handshake of the Bitcoin protocol. It will send the Version message, and block until it receives a VerAck. Once we receive the version, we'll send the verack, and begin downloading. """

        log.debug("handshake (version %s)" % PROTOCOL_VERSION)
        version = Version()
        version.services = 0    # can't send blocks
        log.debug("send Version")
        self.send_message(version)