A district may cause taxes to be levied, in the manner provided in this part, for the purpose of paying any obligation of the district, including its formation expenses and any warrants issued therefor. The amount of this levy shall not exceed the amount permitted by any maximum property tax rate limitation in the Revenue and Taxation Code, provided, however, that if no tax was levied by the district in either the 1971–1972 or 1972–1973 fiscal year and the district incurred expenses in such years, which expenses were paid from revenues other than taxes, then the maximum levy shall not exceed fifty cents ($0.50) per one hundred dollars ($100) of assessed valuation per year.