old_contents: # Prime Factorization - Have the user enter a number
  # and find all Prime Factors (if there are any) and
  # display them.
  
  import math
  
  def is_a_prime(x):
      for i in range(2, x):
          if x % i == 0:
              return False
      return True
  
  # standard boilerplate
  if __name__ == '__main__':
      n = int(raw_input('Enter the number to find prime factors of: '))
  
      factors = []
  
      for i in range(2, n + 1):
          if n % i == 0:
              if is_a_prime(i):
                  factors.append(i)
                  n /= i
      print factors
  
new_contents: # Prime Factorization - Have the user enter a number
  # and find all Prime Factors (if there are any) and
  # display them.
  
  import math
  
  def is_a_prime(x):
      for i in range(2, x):
          if x % i == 0:
              return False
      return True
  
  # standard boilerplate
  if __name__ == '__main__':
      n = int(raw_input('Enter the number to find prime factors of: '))
  
      factors = []
  
      for i in range(2, n + 1):
          while n % i == 0: # Thanks @madsulrik
              if is_a_prime(i):
                  factors.append(i)
                  n /= i
      print factors
  
subject: Print all primes, thanks madsulrik