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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 infixNotation( baseExpr, opList, lpar=Suppress('('), rpar=Suppress(')') ):
 """Helper method for constructing grammars of expressions made up of operators working in a precedence hierarchy. Operators may be unary or binary, left- or right-associative. Parse actions can also be attached to operator expressions. Parameters: - baseExpr - expression representing the most basic element for the nested - opList - list of tuples, one for each operator precedence level in the expression grammar; each tuple is of the form (opExpr, numTerms, rightLeftAssoc, parseAction), where: - opExpr is the pyparsing expression for the operator; may also be a string, which will be converted to a Literal; if numTerms is 3, opExpr is a tuple of two expressions, for the two operators separating the 3 terms - numTerms is the number of terms for this operator (must be 1, 2, or 3) - rightLeftAssoc is the indicator whether the operator is right or left associative, using the pyparsing-defined constants C{opAssoc.RIGHT} and C{opAssoc.LEFT}. - parseAction is the parse action to be associated with expressions matching this operator expression (the parse action tuple member may be omitted) - lpar - expression for matching left-parentheses (default=Suppress('(')) - rpar - expression for matching right-parentheses (default=Suppress(')')) """

    ret = Forward()
    lastExpr = baseExpr | ( lpar + ret + rpar )
    for i,operDef in enumerate(opList):
        opExpr,arity,rightLeftAssoc,pa = (operDef + (None,))[:4]
        termName = "%s term" % opExpr if arity < 3 else "%s%s term" % opExpr
        if arity == 3:
            if opExpr is None or len(opExpr) != 2:
                raise ValueError("if numterms=3, opExpr must be a tuple or list of two expressions")
            opExpr1, opExpr2 = opExpr
        thisExpr = Forward().setName(termName)
        if rightLeftAssoc == opAssoc.LEFT:
            if arity == 1:
                matchExpr = FollowedBy(lastExpr + opExpr) + Group( lastExpr + OneOrMore( opExpr ) )
            elif arity == 2:
                if opExpr is not None:
                    matchExpr = FollowedBy(lastExpr + opExpr + lastExpr) + Group( lastExpr + OneOrMore( opExpr + lastExpr ) )
                else:
                    matchExpr = FollowedBy(lastExpr+lastExpr) + Group( lastExpr + OneOrMore(lastExpr) )
            elif arity == 3:
                matchExpr = FollowedBy(lastExpr + opExpr1 + lastExpr + opExpr2 + lastExpr) + \
                            Group( lastExpr + opExpr1 + lastExpr + opExpr2 + lastExpr )
            else:
                raise ValueError("operator must be unary (1), binary (2), or ternary (3)")
        elif rightLeftAssoc == opAssoc.RIGHT:
            if arity == 1:
                # try to avoid LR with this extra test
                if not isinstance(opExpr, Optional):
                    opExpr = Optional(opExpr)
                matchExpr = FollowedBy(opExpr.expr + thisExpr) + Group( opExpr + thisExpr )
            elif arity == 2:
                if opExpr is not None:
                    matchExpr = FollowedBy(lastExpr + opExpr + thisExpr) + Group( lastExpr + OneOrMore( opExpr + thisExpr ) )
                else:
                    matchExpr = FollowedBy(lastExpr + thisExpr) + Group( lastExpr + OneOrMore( thisExpr ) )
            elif arity == 3:
                matchExpr = FollowedBy(lastExpr + opExpr1 + thisExpr + opExpr2 + thisExpr) + \
                            Group( lastExpr + opExpr1 + thisExpr + opExpr2 + thisExpr )
            else:
                raise ValueError("operator must be unary (1), binary (2), or ternary (3)")
        else:
            raise ValueError("operator must indicate right or left associativity")
        if pa:
            matchExpr.setParseAction( pa )
        thisExpr <<= ( matchExpr.setName(termName) | lastExpr )
        lastExpr = thisExpr
    ret <<= lastExpr
    return ret