old_contents: from st2actions.runners.pythonrunner import Action
  import packer
  import os
  
  
  class BaseAction(Action):
      def __init__(self, config):
          super(BaseAction, self).__init__(config)
          self._exec_path = self.config.get('exec_path', '/opt/packer/bin/packer')
          self._atlas_token = self.config.get('atlas_token', None)
          self._packer = self._get_client()
  
      def _get_client(self):
          if os.path.isfile(self._exec):
              return packer.Packer
          else:
              Exception("Missing packer binary at {}".format(self._exec))
  
new_contents: from st2actions.runners.pythonrunner import Action
  import packer
  import os
  
  
  class BaseAction(Action):
      def __init__(self, config):
          super(BaseAction, self).__init__(config)
          self._exec_path = self.config.get('exec_path', '/opt/packer/bin/packer')
          self._atlas_token = self.config.get('atlas_token', None)
          self._packer = self._get_client()
  
      def _get_client(self):
          if os.path.isfile(self._exec_path):
              return packer.Packer
          else:
              Exception("Missing packer binary at {}".format(self._exec))
  
subject: use the right variable