'Checks whether json_type is a dict or a string. If it is already a dict, it is returned as-is.
If it is not, it is converted to a dict by means of json.loads(json_type)
:param json_type:
:return:'

@staticmethod
def check_json(json_type):

    try:
        str_types = (str, unicode)
    except NameError:
        str_types = (str,)
    if (type(json_type) == dict):
        return json_type
    elif (type(json_type) in str_types):
        return json.loads(json_type)
    else:
        raise ValueError('json_type    should    be    a    json    dict    or    string.')
