Find the number of natural numbers between 30 and 50.
30 50 1 [OP_LIST_ARANGE] [OP_LIST_LEN]
var_a = 30
var_b = 50
var_c = 1
list_a = [i for i in range(var_a, var_b + 1, var_c)]
var_d = len(list_a)
print(int(var_d))