Var. 1; Tasks 6, 7

__main__.py

# -*- coding: utf-8 -*-

def dec_to_base(N, base):
    if not hasattr(dec_to_base, 'table'):        
        dec_to_base.table = '0123456789ABCDEF'       
    x, y = divmod(N, base)        
    return dec_to_base(x, base) + dec_to_base.table[y] if x else dec_to_base.table[y]

num = 16**20+2**30-32
base = 4
need_num = 3
convtd = dec_to_base(num, base)
print("Num:", num)
print("Converted:", convtd)
print("SUM:", sum(map(int, convtd)))
print("Count of", need_num, ":", sum(map(lambda x: 1 if int(x) == need_num else 0, convtd)))