Note 6 - Restricted Cash - Restricted Cash (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jan. 31, 2021	Jul. 31, 2020
Restricted cash, beginning of period	$ 1,839,216	$ 1,821,392
Interest received	84	17,824
Restricted cash, end of period	$ 1,839,300	$ 1,839,216