def get_loc_keywords(loc):
    """
    Return the location keywords based on input loc.

    :param loc: (str) - location of the text
    :return loc_keywords: (list) - list of the location keywords
    """
    loc = loc.lower()
    loc_keywords = []
    if 'top' in loc or 'upper' in loc or 'north' in loc:
        loc_keywords.append('upper')
    elif 'bottom' in loc or 'lower' in loc or 'south' in loc:
        loc_keywords.append('lower')
    if 'right' in loc or 'east' in loc or 'east' in loc:
        loc_keywords.append('right')
    elif 'left' in loc or 'west' in loc:
        loc_keywords.append('left')
    if 'center' in loc or 'middle' in loc:
        loc_keywords.append('center')
    if 'corner' in loc:
        loc_keywords.append('corner')
    return loc_keywords