Proof of proveit.numbers.division.mult_frac_cancel_numer_left theorem

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

%proving mult_frac_cancel_numer_left

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

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