Python Problem:

Test:

Problem 3: Expression simplification For this problem, you will write a function simplifye1 that, given an expression, replaces all subexpressions of the form (*,1, e) or (*,, 1) by e, and replaces all subexpressions of the form (+,0, e), (+, e, 0) (-, e, 0), by e. Note that you have to perform this in recursive fashion, performing the simplification from the bottom up in the expression. To be specific, for an expression (0,e1,e2), you have to first perform the simplification on ei and e2, obtaining e, and e, respectively. Once this is done, you consider the resulting expression (o, e, es), and you perform the simplification on that expression. [] def simplify@1(expr): "Takes an expression expr and returns a simplified version of it, where all subexpressions of the form ('*', 1, e) or ("*', 'e', 1), and all subexpressions of the form ('+', 0, e), ('+', 'e', o), or ('-', 'e', o), are replaced by e, leaving expr otherwise unchanged."" # YOUR CODE HERE raise Not ImplementedError() [ ] ### Feel free to use this cell to write your own tests. ### You will not be graded on what you write here. [ ] ### Tests for 'simplify01': base cases numbers and variables) assert_equal (simplify01 ('x'), 'x') assert_equal (simplify01 ('e'), 'e') assert_equal (simplify01(5), 5) assert_equal(simplify01(O), 0) [ ] ### Tests for simplify01": cases where the expression is unchanged assert_equal(simplify01(('+', 'x', 'x'), ('+', 'x', 'x')) assert_equal(simplify01(('+', 3, 4)), ('+', 3, 4)) assert_equal (simplify@1(('+', 1, 'e'), ('+', 1, 'e')) assert_equal(simplify01(('*', 0, 'e']), ('*', 0, 'e')) # For this problem, don't simplify multiplication by zero assert_equal (simplify01(('*', 'x', ('+', 3, 4))), ('*', 'x', ('+', 3, 4))) assert_equal (simplify01(("*', ('-', 3, 4), 2)), ('*', ('-', 3, 4), 2)) [ ] ### Tests for 'simplify01': single-operator expressions assert_equal (simplify01(('*', 1, 'y')), 'y') assert_equal(simplify01(('*', 6, 1)), 6) assert_equal(simplify01(('+', 0, 'x')), 'x') assert_equal(simplify01(('+', 3, 6)), 3) assert_equal (simplifyi(('-', 'x', 0)), 'x') [ ] ### Tests for "simplify01: more deeply nested expressions assert_equal(simplify01(('-', 8, ('-', 8, 0))), ('-', 8, 8)) assert_equal (simplify01(('+', ('-', 3, 4), ('+', 0, 0))), ('-', 3, 4)) assert_equal(simplify01(('*', ('-', 8, 6), ('-', 10, 0))), ('*', 8, 10)) assert_equal (simplify01(('*', 'x', ('+', 1, ))), 'x') assert_equal (simplify01(c'-', ('*', 1, 6), ('*', 1, 0))), o)