import string


def normalize(token_list):
    """Removing punctuation, numbers and also lowercase conversion"""

    # Building a translate table for punctuation and number removal
    # token_list = [re.findall(r'[0-9]+|[a-z]+', s) for s in token_list]
    # token_list = reduce(operator.add, token_list)
    punctnum_table = str.maketrans({c: None for c in string.punctuation + string.digits})
    rawCorpus_punctnum_rem = [token.translate(punctnum_table) for token in token_list]
    token_ed = [token.lower() for token
                          in rawCorpus_punctnum_rem if token]
    return token_ed