euler_problem_20.py

import argparse
import sys

sys.path.append('/home/gavin/Documents/Git Repositories/project-euler')
import pyfuncs

challenge = 'Find the sum of the digits in {}!:'

import math

parser = argparse.ArgumentParser(description = 'Find the sum of the digits in x!')
parser.add_argument('--num', default = 100, type = int, help = 'Insert x here, it must be a positive integer. It defaults to 100 to correspond with the Project Euler Problem at https://projecteuler.net/problem=20')
x = parser.parse_args().num

if ( (x < 1) and (not isinstance(x, int)) ):
    raise Exception('You entered {}, which is neither an integer nor larger than 1!'.format(x))
if (x < 1):
    raise Exception('You entered {}, which is less than 1, please try a positive integer.'.format(x))
if (not isinstance(x,int)):
    raise Exception('You entered {}, which is not an integer, please try a positive integer.'.format(x))

def euler_20(n):
  result = 0
  for i in str(math.factorial(n)):
    result += int(i)
  return result

pyfuncs.fullprint(challenge,euler_20,x)