Gets a list of all of the context keys referenced in the inputpolicies.Show details from next link. https://docs.aws.amazon.com/ja_jp/cli/latest/reference/iam/get-context-keys-for-custom-policy.html
| aws iam get-context-keys-for-custom-policy and aws iam |
| AWS Identity and Access Management User Guide : http://studylib.net/doc/8360964/aws-identity-and-access-management-user-guide |