Proof of proveit.numbers.number_sets.rational_numbers.nonzero_nonpos_rational_is_rational_neg theorem

import proveit
theory = proveit.Theory() # the theorem's theory

%proving nonzero_nonpos_rational_is_rational_neg

With these allowed/disallowed theorem/theory presumptions (e.g., to avoid circular dependencies), we begin our proof of
nonzero_nonpos_rational_is_rational_neg:
(see dependencies)

nonzero_nonpos_rational_is_rational_neg may now be readily provable (assuming required theorems are usable).  Simply execute "%qed".