def drop_users_to_ignore(ignore, license_lists):
    """This function drops the users to ignore during the comparison from each license type list.

    Parameters
    ----------
    ignore (DataFrame) : Users to ignore during comparison
    license_lists (dict) : dictionary of DataFrames, one for each license type 

    Returns
    -------
    license_lists (dict) : same as input minus DataFrame records whose email matched an email in the *ignore* DataFrame
    """
    for license in license_lists.keys():
        license_lists[license] = license_lists[license][ ~license_lists[license]['User principal name'].isin(ignore['email']) ]
    return license_lists