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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 _chk_gene2go(assoc):
 """Check that associations is gene2go, not go2gene."""

    if not assoc:
        raise RuntimeError("NO ITEMS FOUND IN ASSOCIATIONS {A}".format(A=assoc))
    for key in assoc:
        if isinstance(key, str) and key[:3] == "GO:":
            raise Exception("ASSOCIATIONS EXPECTED TO BE gene2go, NOT go2gene: {EX}".format(
                EX=assoc.items()[:2]))
        return