Return base to the power exp; if mod is present, return base to the power exp, modulo mod (computed more efficiently than pow(base, exp) % mod). The two-argument form pow(base, exp) is equivalent to using the power operator: base**exp.
pow(base, exp, mod=None)>>> pow(38, -1, mod=97)
23
>>> 23 * 38 % 97 == 1
True