Missing necessary parentheses and not allowing equality

[bmw]

In my work on certbot/certbot#9585, unittest2pytest rewrote these lines:

self.assertAlmostEqual(mock_sleep.call_args_list[1][0][0], interval - 1, delta=1)
self.assertAlmostEqual(mock_sleep.call_args_list[2][0][0], interval/2 - 1, delta=1)

as

assert abs(mock_sleep.call_args_list[1][0][0]-interval - 1) < 1
assert abs(mock_sleep.call_args_list[2][0][0]-interval/2 - 1) < 1

This is incorrect for two reasons:

1. Parentheses should be added around the 2nd argument to assertAlmostEqual (or the - 1 changed to + 1).
2. assertAlmostEqual doesn't error if the difference between the first two arguments equals the delta argument.

(With that said, I just ran unittest2pytest on 28k lines of real test code and this was the only problem I encountered other than the pytest.raises limitation described at the bottom of your README. Nice work!)

[RonnyPfannschmidt]

We should have a pytest.approx there instead of the cheap imitation