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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 namedb_state_mutation_sanity_check( opcode, op_data ):
 """ Make sure all mutate fields for this operation are present. Return True if so Raise exception if not """


    # sanity check:  each mutate field in the operation must be defined in op_data, even if it's null.
    missing = []
    mutate_fields = op_get_mutate_fields( opcode )
    for field in mutate_fields:
        if field not in op_data.keys():
            missing.append( field )

    assert len(missing) == 0, ("BUG: operation '%s' is missing the following fields: %s" % (opcode, ",".join(missing)))
    return True