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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 from_seedhex(cls: Type[SigningKeyType], seedhex: str) -> SigningKeyType: """ Return SigningKey instance from Seedhex :param str seedhex: Hexadecimal seed string """

        regex_seedhex = compile("([0-9a-fA-F]{64})")
        match = search(regex_seedhex, seedhex)
        if not match:
            raise Exception('Error: Bad seed hexadecimal format')
        seedhex = match.groups()[0]
        seed = convert_seedhex_to_seed(seedhex)
        return cls(seed)