code: def is_pipeline_variable(var: object) -> bool:
      """Check if the variable is a pipeline variable
  
      Args:
          var (object): The variable to be verified.
      Returns:
           bool: True if it is, False otherwise.
      """
  
      # Currently Expression is on top of all kinds of pipeline variables
      # as well as PipelineExperimentConfigProperty and PropertyFile
      # TODO: We should deprecate the Expression and replace it with PipelineVariable
      return isinstance(var, Expression)
  
imports: from __future__ import absolute_import
  from sagemaker.workflow.entities import Expression
  from sagemaker.workflow.parameters import ParameterString
label_desc: Use image node_id 1 for calling a global function with example usage: is_pipeline_variable(var) and returns: isinstance