Solution for soupstitution Cipher EasyCTF 2018

soupstitution.py

#!/usr/bin/env python3
# coding: utf8

alpha = [chr(i) for i in range(999999) if chr(i).isdigit()][::-1]

def fcn2(txt):
    a = 0
    for c in txt:
        a *= 10
        a += ord(c) - ord('0')
    return a

#flag="७552391"

search = "2365552391"
soluce = chr(2365 + ord('0')) #1st char must be 2365 + ord('0')
i = 5
for _ in range(6):
    for c in alpha:
        m = soluce + c
        f = str(fcn2(m))
        if f[:i] == search[:i]:
            soluce += c
            print(soluce)
            i += 1
            break


print("Soluce: ", soluce)