When, in the opinion of the Bank a special occasion has arisen making it neces­sary or expedient that action should be taken under this section for the purposes of regulating credit in the interests of Indian trade, commerce, industry and agricultural, the Bank may, notwithstanding any limitation contained in section 17,—

(1)

purchase, sell or discount any bill of exchange or promis­sory note though such bill or promissory note is not eligible for purchase or discount by the Bank under that section; or

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(3)

make loans or advances to—