import re, string
def removePunctuation(text):
    """Removes punctuation, changes to lower case, and strips leading and trailing spaces.

    Note:
        Only spaces, letters, and numbers should be retained.  Other characters should be
        eliminated (e.g. it's becomes its).  Leading and trailing spaces should be removed after
        punctuation is removed.

    Args:
        text (str): A string.

    Returns:
        str: The cleaned up string.
    """
    regex = re.compile('[%s]' % re.escape(string.punctuation))
    no_punctuation = regex.sub('', text)
    no_tralling_spaces = no_punctuation.strip()
    lower_case = no_tralling_spaces.lower()
    return lower_case

print removePunctuation('Hi, you!')
print removePunctuation(' No under_score!')
print removePunctuation(' *      Remove punctuation then spaces  * ')