String translation table

string_translate.py

import string

# In [1]: string.punctuation
# Out[1]: '!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~'

# In [2]: string.uppercase
# Out[2]: 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

# In [3]: " " * len(string.punctuation) + string.lowercase
# Out[3]: '                                abcdefghijklmnopqrstuvwxyz'

# translation table maps upper case to lower case and punctuation to spaces
translation_table = string.maketrans(string.punctuation+string.uppercase,
                                     " " * len(string.punctuation) + string.lowercase)

line = ""
line = line.translate(translation_table)

# In [4]: line
# Out[4]: 'foo bar bizz'

word_list = line.split()

# In [5]: word_list
# Out[5]: ['foo', 'bar', 'bizz']