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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 convert_relational(relational):
 """Convert all inequalities to >=0 form. """

    rel = relational.rel_op
    if rel in ['==', '>=', '>']:
        return relational.lhs-relational.rhs
    elif rel in ['<=', '<']:
        return relational.rhs-relational.lhs
    else:
        raise Exception("The relational operation ' + rel + ' is not "
                        "implemented!")