KeyError: ‘user_agent’ in File "/var/task/rest_client.py"

[stevejonpeters]

I'm deploying this quickstart cloudformation template vi AWS CodePipeline.
Lambda error and logged calls are below:
Received event: {
"RequestType": "Create",
"ServiceToken": "arn:aws:lambda:us-west-2:511454808818:function:ndf-databricks-e2-databricksApiFunction-WZtlvtdUT4B4",
"ResponseURL": "https://cloudformation-custom-resource-response-uswest2.s3-us-west-2.amazonaws.com/arn%3Aaws%3Acloudformation%3Aus-west-2%3A511454808818%3Astack/ndf-databricks-e2/017cf290-b3f4-11eb-b31d-0665d51f899d%7CcreateCredentials%7Cab1acd3f-706f-4a3e-a639-61083fabe8c5?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210513T141120Z&X-Amz-SignedHeaders=host&X-Amz-Expires=7200&X-Amz-Credential=AKIA54RCMT6SHRLWK7OU%2F20210513%2Fus-west-2%2Fs3%2Faws4_request&X-Amz-Signature=b511be5ff414e27e138ba2b2e2cb57bdd13ee0233152f6a13618b6588db4fdfd",
"StackId": "arn:aws:cloudformation:us-west-2:511454808818:stack/ndf-databricks-e2/017cf290-b3f4-11eb-b31d-0665d51f899d",
"RequestId": "ab1acd3f-706f-4a3e-a639-61083fabe8c5",
"LogicalResourceId": "createCredentials",
"ResourceType": "Custom::CreateCredentials",
"ResourceProperties": {
"ServiceToken": "arn:aws:lambda:us-west-2:511454808818:function:ndf-databricks-e2-databricksApiFunction-WZtlvtdUT4B4",
"accountId": "9d2c42d8-63ec-468b-8e8a-60d32656ea73",
"credentials_name": "e2-dev-credentials",
"role_arn": "arn:aws:iam::511454808818:role/ndf-databricks-e2-cross-account",
"encodedbase64": "ZGF0YWVuZ2luZWVyc0B3ZXN0ZXJuZ292ZXJub3JzdW5pdmVyc2l0eS5vbm1pY3Jvc29mdC5jb206SVJAd2d1LjNkdQ==",
"action": "CREATE_CREDENTIALS"
}
}

[ERROR] 2021-05-13T14:11:21.467Z 4030b1ba-8f0f-40e8-a9c0-924094ef7191 Exception: 'user_agent'
Traceback (most recent call last):
File "/var/task/rest_client.py", line 45, in handler
event['ResourceProperties']['user_agent']
KeyError: ‘user_agent'

Received event: {
"RequestType": "Create",
"ServiceToken": "arn:aws:lambda:us-west-2:511454808818:function:ndf-databricks-e2-databricksApiFunction-WZtlvtdUT4B4",
"ResponseURL": "https://cloudformation-custom-resource-response-uswest2.s3-us-west-2.amazonaws.com/arn%3Aaws%3Acloudformation%3Aus-west-2%3A511454808818%3Astack/ndf-databricks-e2/017cf290-b3f4-11eb-b31d-0665d51f899d%7CcreateStorageConfiguration%7Cac211c79-7589-47ee-84bf-6f94e34a1b0b?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210513T141120Z&X-Amz-SignedHeaders=host&X-Amz-Expires=7199&X-Amz-Credential=AKIA54RCMT6SHRLWK7OU%2F20210513%2Fus-west-2%2Fs3%2Faws4_request&X-Amz-Signature=0da903098b466721150682bcf8f86e1cd07a04b05a1a40b18325ac656ea44ef4",
"StackId": "arn:aws:cloudformation:us-west-2:511454808818:stack/ndf-databricks-e2/017cf290-b3f4-11eb-b31d-0665d51f899d",
"RequestId": "ac211c79-7589-47ee-84bf-6f94e34a1b0b",
"LogicalResourceId": "createStorageConfiguration",
"ResourceType": "Custom::CreateStorageConfigurations",
"ResourceProperties": {
"ServiceToken": "arn:aws:lambda:us-west-2:511454808818:function:ndf-databricks-e2-databricksApiFunction-WZtlvtdUT4B4",
"accountId": "9d2c42d8-63ec-468b-8e8a-60d32656ea73",
"storage_config_name": "e2-dev-storage",
"encodedbase64": "ZGF0YWVuZ2luZWVyc0B3ZXN0ZXJuZ292ZXJub3JzdW5pdmVyc2l0eS5vbm1pY3Jvc29mdC5jb206SVJAd2d1LjNkdQ==",
"s3bucket_name": "databrickes-e2-dev",
"action": "CREATE_STORAGE_CONFIGURATIONS"
}
}

[ERROR] 2021-05-13T14:11:21.277Z b0015d99-81d9-4c77-beec-4703109b4bbc Exception: 'user_agent'
Traceback (most recent call last):
File "/var/task/rest_client.py", line 56, in handler
event['ResourceProperties']['user_agent']
KeyError: ‘user_agent’