docs: Add code sample for Pipelines (#684)

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Fixes #683 🦕

README.rst

@@ -349,6 +349,47 @@ To delete an endpoint:
   endpoint.delete()
 
 
+Pipelines
+---------
+
+To create a Vertex Pipeline run:
+
+.. code-block:: Python
+
+  # Instantiate PipelineJob object
+  pl = PipelineJob(
+      # Display name is required but seemingly not used
+      # see https://github.com/googleapis/python-aiplatform/blob/9dcf6fb0bc8144d819938a97edf4339fe6f2e1e6/google/cloud/aiplatform/pipeline_jobs.py#L260
+      display_name="My first pipeline",
+
+      # Whether or not to enable caching
+      # True = always cache pipeline step result
+      # False = never cache pipeline step result
+      # None = defer to cache option for each pipeline component in the pipeline definition
+      enable_caching=False,
+
+      # Local or GCS path to a compiled pipeline definition
+      template_path="pipeline.json",
+
+      # Dictionary containing input parameters for your pipeline
+      parameter_values=parameter_values,
+
+      # GCS path to act as the pipeline root
+      pipeline_root=pipeline_root,
+  )
+
+  # Execute pipeline in Vertex
+  pl.run(
+    # Email address of service account to use for the pipeline run
+    # You must have iam.serviceAccounts.actAs permission on the service account to use it
+    service_account=service_account,
+
+    # Whether this function call should be synchronous (wait for pipeline run to finish before terminating)
+    # or asynchronous (return immediately)
+    sync=sync
+  )
+
+
 Explainable AI: Get Metadata
 ----------------------------