2. Summary of Significant Accounting Policies (Details - Property and Equipment) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Property and equipment, gross	$ 58,549	$ 44,746
Less: Accumulated depreciation and amortization	(21,094)	(17,641)
Total property and equipment, net	37,455	27,105
Leasehold Improvements [Member]
Property and equipment, gross	23,000	21,130
Laboratory and manufacturing equipment [Member]
Property and equipment, gross	20,793	15,033
Computer Equipment and software [Member]
Property and equipment, gross	5,541	5,334
Furniture, fixtures and office equipment [Member]
Property and equipment, gross	843	685
Construction in Progress [Member]
Property and equipment, gross	$ 8,372	$ 2,564

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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