1. fix the way to parse response using list-parsing instead of dict-parsing.

1. rewrite the procedure of recieving response and make it more readable.
2. add some checks to confirm which conditions that developers encounter.

Summary of changes:
1. add AuthorizationError and msg for hint
2. add response as a part of error msg for reminder.

Summary of changes:
1. cancel AuthorizationError and msg for hint (because of reducing the complexity of hints.)

    Summary of changes:
    1. add unit test
    2. add checks for parameters.
    3. change the response checks and wordings.

        Summary of changes:
        1. add test case for missing api key.
        2. add check for api key.
        3. change the way when calling auth error.

Summary of changes:
1. revise test case of testing api key.
2. remove default value from project_id.
3. rewrite condition and exception content to check response.