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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 get_key(self, compressed=None):
 """Get the hex-encoded key. :param compressed: False if you want a standard 65 Byte key (the most standard option). True if you want the compressed 33 Byte form. Defaults to None, which in turn uses the self.compressed attribute. :type compressed: bool PublicKeys consist of an ID byte, the x, and the y coordinates on the elliptic curve. In the case of uncompressed keys, the ID byte is 04. Compressed keys use the SEC1 format: If Y is odd: id_byte = 03 else: id_byte = 02 Note that I pieced this algorithm together from the pycoin source. This is documented in http://www.secg.org/collateral/sec1_final.pdf but, honestly, it's pretty confusing. I guess this is a pretty big warning that I'm not *positive* this will do the right thing in all cases. The tests pass, and this does exactly what pycoin does, but I'm not positive pycoin works either! """

        if compressed is None:
            compressed = self.compressed
        if compressed:
            parity = 2 + (self.y & 1)  # 0x02 even, 0x03 odd
            return ensure_bytes(
                long_to_hex(parity, 2) +
                long_to_hex(self.x, 64))
        else:
            return ensure_bytes(
                b'04' +
                long_to_hex(self.x, 64) +
                long_to_hex(self.y, 64))