def get_polysemy_class(num_senses):
    """
    Converts the number of senses (integer) in several ranges
    """
    polysemy_class = None
    if num_senses == 0:
        polysemy_class = '0'
    elif num_senses == 1:
        polysemy_class = 'mono'
    elif num_senses < 5:
        polysemy_class = 'low_polysemy'
    elif num_senses < 15:
        polysemy_class = 'medium_polysemy'
    elif num_senses < 30:
        polysemy_class = 'high_polysemy'
    else:
        polysemy_class = 'very_high_polysemy'
    return polysemy_class