class Aws::CredentialProviderChain

def env_credentials(_options)
  key =    %w[AWS_ACCESS_KEY_ID AMAZON_ACCESS_KEY_ID AWS_ACCESS_KEY]
  secret = %w[AWS_SECRET_ACCESS_KEY AMAZON_SECRET_ACCESS_KEY AWS_SECRET_KEY]
  token =  %w[AWS_SESSION_TOKEN AMAZON_SESSION_TOKEN]
  Credentials.new(envar(key), envar(secret), envar(token))
end