Proof of proveit.logic.booleans.implication.true_iff_false_negated theorem

import proveit
from proveit.logic.booleans.implication import iff_t_f
theory = proveit.Theory() # the theorem's theory

%proving true_iff_false_negated

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

true_iff_false_negated has been proven.  Now simply execute "%qed".

%qed

proveit.logic.booleans.implication.true_iff_false_negated has been proven.

	step type	requirements	statement
0	instantiation	1, 2	⊢
	:
1	theorem		⊢
	proveit.logic.booleans.negation.negation_intro
2	theorem		⊢
	proveit.logic.booleans.implication.iff_t_f