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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 read_short(source, offset):
 """Reads a number from a byte array. :param bytes source: Source byte string :param int offset: Point in byte string to start reading :returns: Read number and offset at point after read data :rtype: tuple of ints :raises: SerializationError if unable to unpack """

    try:
        (short,) = struct.unpack_from(">H", source, offset)
        return short, offset + struct.calcsize(">H")
    except struct.error:
        raise SerializationError("Bad format of serialized context.")