deepcopy vs list comprension

test.py

from copy import deepcopy
from timeit import Timer


list_o_lists = [[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4]]

def deepcopy_f():
    meh = deepcopy(list_o_lists)

def slice_f():                                                   
    meh = [li[:] for li in list_o_lists]
                                                                    
deepcopy_t = Timer("deepcopy_f()", "from __main__ import deepcopy_f, list_o_lists")
slice_t = Timer("slice_f()", "from __main__ import slice_f, list_o_lists")

print("deepcopy: %s" % deepcopy_t.timeit(number=1000))                                                       
print("slice:    %s" % slice_t.timeit(number=1000))

"""OSX 10.7.2 pypy 1.7.0
deepcopy: 0.0895478725433
slice:    0.00567483901978
"""

"""OSX 10.7.2 python 2.7.2
deepcopy: 0.0501799583435
slice:    0.00181603431702
"""

1 million reps

OSX 10.7.2 pypy 1.7.0
deepcopy: 4.24665093422
slice: 0.431082963943

OSX 10.7.2 cpython 2.7.2
deepcopy: 48.4800450802
slice: 1.80412483215