Hyunji gave 7 of the 20 pencils to Hyeonseung and again received 5 from Taewoo. Find how many pencils Hyunji has.
20 7 [OP_SUB] 5 [OP_ADD]
var_a = 20
var_b = 7
var_c = var_a - var_b
var_d = 5
var_e = var_c + var_d
print(int(var_e))