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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 to_sdp(self):
 """ Return a string representation suitable for SDP. """

        sdp = '%s %d %s %d %s %d typ %s' % (
            self.foundation,
            self.component,
            self.transport,
            self.priority,
            self.host,
            self.port,
            self.type)
        if self.related_address is not None:
            sdp += ' raddr %s' % self.related_address
        if self.related_port is not None:
            sdp += ' rport %s' % self.related_port
        if self.tcptype is not None:
            sdp += ' tcptype %s' % self.tcptype
        if self.generation is not None:
            sdp += ' generation %d' % self.generation
        return sdp