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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 send_pid(cls, sock, pid):
 """Send the PID chunk over the specified socket."""

    assert(isinstance(pid, IntegerForPid) and pid > 0)
    encoded_int = cls.encode_int(pid)
    cls.write_chunk(sock, ChunkType.PID, encoded_int)