Jenkinsfile

stage('TEST STATE') {
  steps {
    script {
      withJenkinsCreds {
        sh "python3.7 ./var/testStuff.py"        
      }
    }
  }
}

withJenkinsCreds.groovy

def call(c) {
    withCredentials ([string(credentialsId: 'jenkins-test-cred-1', variable: 'TEST_CRED_1'), 
                                string(credentialsId: 'jenkins-test-cred-2', variable: 'TEST_CRED_2'),
                                string(credentialsId: 'jenkins-test-cred-3, variable: 'TEST_CRED_3')]){
            c()
        }
    }
}