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This was brought up on the LGTM.com forums here: https://discuss.lgtm.com/t/warn-when-always-failing-assert-is-reachable-rather-than-unreachable/2436 Essentially, in a complex chain of `elif` statements, like ```python if x < 0: ... elif x >= 0: ... else: ... ``` the `else` clause is redundant, since the preceding conditions completely exhaust the possible values for `x` (assuming `x` is an integer). Rather than promoting the final `elif` clause to an `else` clause, it is common to instead raise an explicit exception in the `else` clause. During execution, this exception will never actually be raised, but its presence indicates that the preceding conditions are intended to cover all possible cases. I think it's a fair point. This is a clear instance where the alert, even if it is technically correct, is not useful for the end user. Also, I decided to make the exclusion fairly restrictive: it only applies if the unreachable statement is an `assert False, ...` or `raise ...`, and only if said statement is the first in the `else` block. Any other statements will still be reported.