New to Python - Want code review of simple combination routine

[Michael Bauers]

I am posting a routine I wrote to return a list of combinations.  The input
to 'combination' is a list, and 'n' which represents the number of elements
to take in combination.  If you forgot your math, [1,2,3] with n=2 should
give [[1,2], [1,3], [2,3]]

Because I am new to Python, I am not sure I wrote this the most efficient
way.  I would appreciate feedback on this code.  This would help me know
whether I am understanding how to code in Python correctly.


The algorithm works like this:
left list       right list
[]              [1,2,3]
   call combination2()
[1]            [2,3] - move 1 to left list
call combination 2
[1,2]         [3]  - move 2 to left list, add [1,2] to result list
[1]            [3] - Remove 2 from left list
[1,3]         [] - Move 3 to left list, add [1,3] to result list
   - return from recursive call to combination2() 
[1]            [2,3] - after call, same as before
[2]            [3] - Remove 1 from left list, move 2 from right list to left
list
call combination 2
[2,3]         [] - move 3 to left list, add [2,3] to result list



********************** Python code ***********************
import copy

def combinations(list, n):
   if n > len(list):
      return []
   comb_list = []
   r = combinations2([], list, n, comb_list)
   return comb_list

def combinations2(l_list, r_list, n, result_list):
   if (len(r_list) == 0 or n == 0):
      return copy.copy(l_list)
   else:
      temp_l_list = copy.copy(l_list)
      temp_r_list = copy.copy(r_list)
      for i in r_list:
         temp_r_list.remove(i)
         temp_l_list.append(i)
         if n == 1:
            result_list.append(copy.copy(temp_l_list))
         else:    
            combinations2(temp_l_list, temp_r_list, n - 1,
                          result_list)
         temp_l_list.remove(i)