my_service_account_file.json

# I put this in here just so that you'll know what a service account looks like in JSON format.  Obviously, you'll need your own to actually use Google BigQuery.
{
  "type": "service_account",
  "project_id": "xxxxxxxx103",
  "private_key_id": "xxxxxxx262dcd6df4bd0fcee33c12xxxx",
  "private_key": "-----BEGIN PRIVATE KEY-----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\nxtRwQlBlolUImaUNFpYwOQ==OBVIOUSLY_THIS_ISN'T_A_REAL_SERVICE_ACCOUNT..GET_YOUR_OWN\n-----END PRIVATE KEY-----\n",
  "client_email": "XXX-appengine-service@XXXX-1103.iam.gserviceaccount.com",
  "client_id": "116868686051XXX",
  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
  "token_uri": "https://accounts.google.com/o/oauth2/token",
  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/xxxx-appengine-service%40xxxx-1103.iam.gserviceaccount.com"
}