import re


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 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.
    """
    #<FILL IN>
    t1 = text.lower()
    t2 = re.sub(r'[^0-9a-z\s]',"",t1)
    t3 = t2.strip()
    return t3