'Turn URL string into parameters.'

@staticmethod
def _split_url_string(param_str):

    if (not PY3):
        param_str = b(param_str, 'utf-8')
    parameters = parse_qs(param_str, keep_blank_values=True)
    for (k, v) in parameters.items():
        if (len(v) == 1):
            parameters[k] = unquote(v[0])
        else:
            parameters[k] = sorted([unquote(s) for s in v])
    return parameters
