The following is a python property-based test using the Hypothesis library: from hypothesis import given, strategies as st from hypothesis import assume expression = st.deferred(lambda: st.one_of( st.integers(),   st.tuples(st.just('+'), expression, expression),                st.tuples(st.just(' '), expression, expression), n def div_subterms(e):   if isinstance(e, int):      return True    if e[0] == '\/' and e[-1] == 0:    return False return div_subterms(e[1]) and div_subterms(e[2]) def evaluate(e):               return e     elif e[0] == '+': return evaluate(e[1]) + evaluate(e[2])    else:  assert e[0] == '\/'    return evaluate(e[1]) evaluate(e[2]) @given(expression) def test(e): assume(div_subterms(e))   evaluate(e) There is a bug in this program triggered by the input               (', -492, (, -90, -268)). Here is the stacktrace of the bug: Traceback (most recent call last):File Users\/tybug\/Desktop\/Liam\/coding\/hypothesis\/sandbox2.py\, line 34, in test evaluate(e)File Users\/tybug\/Desktop\/Liam\/coding\/hypothesis\/sandbox2.py\, line 27, in evaluate               return evaluate(e[1])evaluate(e[2]);ZeroDivisionError: integer division or modulo by zero Please suggest a simpler and or smaller input which would also trigger this bug. Do not give any explanation. Only state the simpler input