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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 compress(x, y):
 """ Given a x,y coordinate, encode in "compressed format" Returned is always 33 bytes. """

    polarity = "02" if y % 2 == 0 else "03"

    wrap = lambda x: x
    if not is_py2:
        wrap = lambda x: bytes(x, 'ascii')

    return unhexlify(wrap("%s%0.64x" % (polarity, x)))