Show the Proof

import proveit
# Automation is not needed when only showing a stored proof:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%show_proof

	step type	requirements	statement
0	instantiation	1, 2, 3	,  ⊢
	: , : , :
1	theorem		⊢
	proveit.logic.sets.inclusion.unfold_subset_eq
2	instantiation	4, 5, 6	⊢
	: , : , :
3	instantiation	7, 8	,  ⊢
	:
4	theorem		⊢
	proveit.logic.sets.cartesian_products.cart_exp_subset_eq
5	theorem		⊢
	proveit.numbers.numerals.decimals.posnat3
6	instantiation	9, 10	⊢
	: , :
7	assumption		⊢
8	instantiation	11, 12, 13	⊢
	:
9	theorem		⊢
	proveit.logic.sets.inclusion.relax_proper_subset
10	theorem		⊢
	proveit.numbers.number_sets.complex_numbers.real_within_complex
11	theorem		⊢
	proveit.numbers.number_sets.integers.nonneg_int_is_natural
12	instantiation	28, 14, 26	⊢
	: , : , :
13	instantiation	15, 16	⊢
	: , :
14	instantiation	17, 24, 25	⊢
	: , :
15	theorem		⊢
	proveit.numbers.ordering.relax_less
16	instantiation	18, 19, 20	⊢
	: , : , :
17	theorem		⊢
	proveit.numbers.number_sets.integers.int_interval_within_int
18	theorem		⊢
	proveit.numbers.ordering.transitivity_less_less_eq
19	instantiation	21, 22	⊢
	:
20	instantiation	23, 24, 25, 26	⊢
	: , : , :
21	theorem		⊢
	proveit.numbers.number_sets.natural_numbers.natural_pos_is_pos
22	theorem		⊢
	proveit.numbers.numerals.decimals.posnat2
23	theorem		⊢
	proveit.numbers.number_sets.integers.interval_lower_bound
24	instantiation	28, 29, 27	⊢
	: , : , :
25	instantiation	28, 29, 30	⊢
	: , : , :
26	assumption		⊢
27	theorem		⊢
	proveit.numbers.numerals.decimals.nat2
28	theorem		⊢
	proveit.logic.sets.inclusion.superset_membership_from_proper_subset
29	theorem		⊢
	proveit.numbers.number_sets.integers.nat_within_int
30	theorem		⊢
	proveit.numbers.numerals.decimals.nat4