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This documetnation is for a Third Partt Party resource that may be subject to chage change without notice.
The official
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documentation should be
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referred to in the event the instructions
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do not match up.
Setting Up OAuth2 Authentication:
https://support.google.com/cloud/answer/6158849
Enabling GMAIL APIS
https://developers.google.com/identity/protocols/oauth2/web-server#enable-apis
Creating a Service Account
https://support.google.com/a/answer/7378726
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