new_contents: #!/usr/bin/env python
  
  """
  You are given a positive integer. Your function should calculate the product of the digits excluding any zeroes.
  
  For example: The number given is 123405. The result will be 1*2*3*4*5=120 (don't forget to exclude zeroes).
  
  Input: A positive integer.
  
  Output: The product of the digits as an integer.
  
  
  """
  
  from functools import reduce
  
  checkio = lambda number: reduce(lambda res, x: res*x, [int(num) for num in str(number) if int(num)], 1)
  
  # These "asserts" using only for self-checking and not necessary for auto-testing
  if __name__ == '__main__':
      assert checkio(123405) == 120
      assert checkio(999) == 729
      assert checkio(1000) == 1
      assert checkio(1111) == 1
  
subject: Add Solve Digit Multiplication