@staticmethod
def _get_param_args(options):
    """
        Find which values a filter can take

        Args:
            options (BeautifulSoup?): a parsed <SELECT> tag with desired format and values

        Returns:
            {str: str}: each possible value as a key, its corresponding url code as the value
        """
    args = {}
    for option in options:
        number = option['value'].replace(',', '')
        value = option.text.replace('\n', '')
        if value[-1] == ')':
            right_paren_location = -1 * (len(value) - value.rfind('('))
            value = value[:right_paren_location].strip()
        args[value] = number
    return args
