DialogflowのAPIv2をpythonで実装したい。

DialogflowのAPIにv2が出たということなので、ローカル環境で動作するようにv1からの切り替え作業を行っているのですが、エラーが出てしまい困っています。
どのように対処したらよいのでしょうか。
また、session_idについて、v2ではどこから取得すればいいのかがよくわかっていません。
session_idはどのように扱えばいいのでしょうか。

■環境
python3.4.5

■参考にしたサイト
https://dialogflow-python-client-v2.readthedocs.io/en/latest/
こちらのDetecting Intent (Texts)を参考にしています。

■APIのコード

local.py
1project_id = "プロジェクトのID"
2session_id = ""
3language_code = "ja"
4session_client = dialogflow.SessionsClient()
5
6session = session_client.session_path(project_id, session_id)
7
8text_input = dialogflow.types.TextInput(text=query, language_code=language_code)
9query_input = dialogflow.types.QueryInput(text=text_input)
10response = session_client.detect_intent(session=session, query_input=query_input)
11print('Query text: {}'.format(response.query_result.query_text))
12print('Detected intent: {} (confidence: {})\n'.format(response.query_result.intent.display_name,response.query_result.intent_detection_confidence))
13print('Fulfillment text: {}\n'.format(response.query_result.fulfillment_text))

■コード実行時のエラー

2018-08-06 17:43:45,347 _default.py 303 WARNING No project ID could be determined. Consider running `gcloud config set project` or setting the GOOGLE_CLOUD_PROJECT environment variable
Traceback (most recent call last):
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\grpc_helpers.py", line 54, in error_remapped_callable
    return callable_(*args, **kwargs)
  File "C:\Anaconda3\envs\py34\lib\site-packages\grpc\_channel.py", line 514, in __call__
    return _end_unary_response_blocking(state, call, False, None)
  File "C:\Anaconda3\envs\py34\lib\site-packages\grpc\_channel.py", line 448, in _end_unary_response_blocking
    raise _Rendezvous(state, None, None, deadline)
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
        status = StatusCode.PERMISSION_DENIED
        details = "Dialogflow API has not been used in project 563584335869 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/dialogflow.googleapis.com/overview?project=563584335869 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry."
        debug_error_string = "{"created":"@1533545026.267000000","description":"Error received from peer","file":"src/core/lib/surface/call.cc","file_line":1095,"grpc_message":"Dialogflow API has not been used in project 563584335869 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/dialogflow.googleapis.com/overview?project=563584335869 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry.","grpc_status":7}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "local.py", line 42, in <module>
    response = session_client.detect_intent(session=session, query_input=query_input)
  File "C:\Anaconda3\envs\py34\lib\site-packages\dialogflow_v2\gapic\sessions_client.py", line 270, in detect_intent
    request, retry=retry, timeout=timeout, metadata=metadata)
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\gapic_v1\method.py", line 139, in __call__
    return wrapped_func(*args, **kwargs)
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\retry.py", line 260, in retry_wrapped_func
    on_error=on_error,
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\retry.py", line 177, in retry_target
    return target()
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\timeout.py", line 206, in func_with_timeout
    return func(*args, **kwargs)
  File "C:\Anaconda3\envs\py34\lib\site-packages\google\api_core\grpc_helpers.py", line 56, in error_remapped_callable
    six.raise_from(exceptions.from_grpc_error(exc), exc)
  File "<string>", line 3, in raise_from
google.api_core.exceptions.PermissionDenied: 403 Dialogflow API has not been used in project 563584335869 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/dialogflow.googleapis.com/overview?project=563584335869 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry.