class_docstr: Helper methods for Vertex Handler.
class_docstr_tok: ["Helper","methods","for","Vertex","Handler","."]
docstr: List all the pipelines in the environment.
docstr_tok: ["List","all","the","pipelines","in","the","environment","."]
code: def list_pipelines(self) -> None:
      """List all the pipelines in the environment."""
      # There is no managed storage for pipeline packages, so CLI consults
      # local dir to list pipelines.
      if not fileio.exists(self._handler_home_dir):
          click.echo("No pipelines to display.")
          return
      pipelines_list = fileio.listdir(self._handler_home_dir)
  
      # Print every pipeline name in a new line.
      click.echo("-" * 30)
      click.echo("\n".join(pipelines_list))
      click.echo("-" * 30)
  
imports: import functools
  import os
  import sys
  import click
  from google.cloud import aiplatform
  from google.cloud.aiplatform import pipeline_jobs
  from tfx.dsl.io import fileio
  from tfx.tools.cli import labels
  from tfx.tools.cli.handler import base_handler
  from tfx.tools.cli.handler import kubeflow_handler
  from tfx.tools.cli.handler import kubeflow_v2_dag_runner_patcher
  from tfx.utils import io_utils
label_desc: Use image node_id 3 for calling the VertexHandler obj's underlying member method code with example usage: obj.list_pipelines() without return types