title: I'm trying to run a pipeline using python slaves on Jenkins but somehow it's always shows this output : jenkins doesn't have label 'python'
body: <p>So, i'm running the jenkins image on openshift 3.11 server and i'm trying to run a pipeline on Jenkins but somehow i can't use jenkins python slave, it's always shows this command when i'm trying to build the pipeline : jenkins doesn't have label 'python'</p>
  
  <p>The thing is if i'm changed the label to 'master' it works but doesn't produce the output that i'm expected.</p>
  
  <p>This is the kubernetes pod &amp; container template config :
  Name : python 
  Labels: python 
  Container Template: 
  Name: jnlp 
  Docker Image: idealo/jenkins-slave-python-centos7:latest 
  Always pull image: True 
  Working directory: /tmp 
  Arguments to pass to the command: ${computer.jnlpmac}${computer.name}</p>
  
  <p>Also the only active node in Jenkins nodes was master node and nothing else. P.S. the git repository was a private repository.</p>
  
  <pre><code>#This is the jenkinsfile for the pipeline
  
  pipeline {
      agent {
            node {
                label 'python' 
            }
      }
      environment {
          APPLICATION_NAME = 'abc'
          GIT_REPO="https://gitlab.playcourt.id/user/abc.git"
          GIT_BRANCH="master"
          STAGE_TAG = "promoteToQA"
          DEV_PROJECT = "test-cicd"
          STAGE_PROJECT = "myproject"
          TEMPLATE_NAME = "abc"
          ARTIFACT_FOLDER = "target"
          PORT = 8080;
          passwd = 123;
      }
      stages {
           stage('Get Latest Code') {
              steps {
                  withCredentials([usernamePassword(credentialsId: 'abc', passwordVariable: 'user', usernameVariable: 'user')]) {
                          sh('git pull https://${user}:${user}@gitlab.playcourt.id/user/abc.git')
                      }
              }
          }
  
  #etc..
  </code></pre>
  
  <p>It always shows an output "Jenkins doesn't have label 'python'"
  Any help or feedback would be great, thanks!</p>