Using 1, 7, 4, and 3 only once, find the difference between the largest three-digit number whose tens digit is 3 and the third largest three-digit number.
[OP_LIST_SOL] 1 7 4 3 [OP_LIST_EOL] 3 [OP_LIST_GET_PERM] 10 3 [OP_LIST_SEARCH_FIXED_DIGIT] 1 [OP_LIST_MAX] 3 [OP_LIST_MAX] [OP_SUB] [OP_ABS]
var_a = 1
var_b = 7
var_c = 4
var_d = 3
list_a= []
if "/" in str(var_d):
    var_d = eval(str(var_d))
list_a.append(var_d)
if "/" in str(var_c):
    var_c = eval(str(var_c))
list_a.append(var_c)
if "/" in str(var_b):
    var_b = eval(str(var_b))
list_a.append(var_b)
if "/" in str(var_a):
    var_a = eval(str(var_a))
list_a.append(var_a)
list_a.reverse()
var_e = 3
list_b = [str(i) for i in list_a]
list_b = list(itertools.permutations(list_b, var_e))
list_b = [''.join(num_list) for num_list in list_b]
list_b = [str_num for str_num in list_b if str_num[0] != '0']
list_b = [float(i) for i in list_b]
var_f = 10
var_g = 3
list_c = [] 
var_f = int(var_f)
var_g = int(var_g)
for i in list_b:
    i = int(i)
    if (i//var_f)%10 == var_g:
        list_c.append(i)
var_h = 1
list_d=list_c.copy()
list_d.sort()
var_i = list_d[-var_h]
var_j = 3
list_e=list_c.copy()
list_e.sort()
var_k = list_e[-var_j]
var_l = var_i - var_k
var_m = abs(var_l)
print(int(var_m))