title: Calculate the LCM of a list of given numbers in Python
body: <p>I have written a code to find out the LCM (Lowest Common Multiple) of a list of numbers but there appears to be an error in my code. The code is given below:</p>
  
  <pre><code>def final_lcm(thelist):
     previous_thelist = thelist
     prime_thelist = list(set(thelist) - set(returns_new_thelist(previous_thelist))
     factors = 1
     for i in prime_thelist:
         factors = factors*i
     new_thelist = returns_new_thelist(previous_thelist)
     for i in range(1, 10000000000):
         s_empty = []
         for j in new_thelist:
             if i % j  == 0:
                 s_empty.append(True)
         if len(new_thelist) == len(s_empty):
             initial_lcm = i
             break
     final_lcm = factor*initial_lcm
     return final_lcm
  
  
  
  def returns_new_thelist(ll):
      if 3 in ll:
          ll.remove(3)
      for i in ll:
          if checks_if_prime(i) == True:
              ll.remove(i)
      return ll    
  
  def checks_if_prime(n):
      if n == 2:
      return True
      import math
      for i in range(math.ceil(0.5*n), 1, -1):
          if n % i == 0:
              return False
          elif i == 2:
              return True
  
  print(final_lcm([1,2,3,4,5,6,7,8,9]))
  </code></pre>
  
  <p>Kindly pardon my poor choice of variables, I request you to see if the logic is correct and that the code is functional. </p>
  
  <p>The syntax error which I am getting is <strong>that "factors" is invalid syntax</strong> though I don't agree with this. Please tell me where my code is wrong. </p>