A. A bank may accept:

(1)     a draft which has not more than one hundred eighty days sight to run, exclusive of days of grace, and is drawn to finance the purchase of goods, with maturity in accordance with the original terms of purchase, or is secured by shipping documents transferring or securing title to goods or by receipt of a licensed or bonded warehouse or elevator transferring or securing title to readily marketable, nonperishable staples;

and (2)     a draft which has no more than ninety days sight to run, exclusive of days of grace, and is drawn by a bank outside the continental limits of the United States for the purpose of furnishing dollar exchange for trade.

B. A bank may issue a letter of credit, but unless the authority conferred to draw upon the bank or its correspondents is limited to such drafts as a bank is authorized by this section to accept, the amount of the credit outstanding at any one time shall be deemed to be a loan to the person for whose account the credit was issued.