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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 groestlHash(data):
 """Groestl-512 compound hash."""

    try:
        import groestlcoin_hash
    except ImportError:
        t = 'Groestlcoin requires the groestlcoin_hash package ("pip install groestlcoin_hash").'
        print(t)
        raise ImportError(t)

    return bytes_as_revhex(groestlcoin_hash.getHash(data, len(data)))