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Login to the Google Cloud Platform console.
Select the following icon (Navigation menu) > APIs & Services tab > select Credentials.
Select the required project.
Create a service account.
Tip: If there is already an existing service account for a project that can be shared, manage that service account. Click Manage service accounts to manage an existing service account.Click Create service account.
Enter the name for the service account, ID for the service account, and description for the service account.
Click Create.
Assign the following roles to the selected project to grant permissions for the resources in the project.
Compute Admin
BigQuery Data Owner
BigQuery Job User
Click Continue.
Click Done.
Create private key and download generated json.
On the Service Accounts page, select the required email address to create a key for it.
Select the Keys tab, and in the ADD KEY list select Create new key.
On the Create private key for Project_name page, select JSON as the Key type.
Download the JSON file.
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