Proof of proveit.numbers.ordering.non_neg_if_real_non_neg theorem

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

%proving non_neg_if_real_non_neg

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

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