Update and add Cloud KMS samples [(#3690)](#3690)

This updates the Cloud KMS samples to match the format from the other 6
languages. It also updates the samples to note the workaround for
googleapis/gapic-generator-python#364.

kms/attestations/README.rst

@@ -0,0 +1,74 @@
+.. This file is automatically generated. Do not edit this file directly.
+
+Google Cloud Key Management Service Python Samples
+===============================================================================
+
+.. image:: https://gstatic.com/cloudssh/images/open-btn.png
+   :target: https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=kms/attestations/README.rst
+
+
+This directory contains samples for Google Cloud Key Management Service. The `Cloud Key Management Service`_ allows you to create, import, and manage cryptographic keys and perform cryptographic operations in a single centralized cloud service.
+
+
+
+
+.. _Google Cloud Key Management Service: https://cloud.google.com/kms/docs/
+
+Setup
+-------------------------------------------------------------------------------
+
+
+Install Dependencies
+++++++++++++++++++++
+
+#. Clone python-docs-samples and change directory to the sample directory you want to use.
+
+    .. code-block:: bash
+
+        $ git clone https://github.com/GoogleCloudPlatform/python-docs-samples.git
+
+#. Install `pip`_ and `virtualenv`_ if you do not already have them. You may want to refer to the `Python Development Environment Setup Guide`_ for Google Cloud Platform for instructions.
+
+   .. _Python Development Environment Setup Guide:
+       https://cloud.google.com/python/setup
+
+#. Create a virtualenv. Samples are compatible with Python 2.7 and 3.4+.
+
+    .. code-block:: bash
+
+        $ virtualenv env
+        $ source env/bin/activate
+
+#. Install the dependencies needed to run the samples.
+
+    .. code-block:: bash
+
+        $ pip install -r requirements.txt
+
+.. _pip: https://pip.pypa.io/
+.. _virtualenv: https://virtualenv.pypa.io/
+
+Samples
+-------------------------------------------------------------------------------
+
+Verify attestations for keys generated by Cloud HSM
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+.. image:: https://gstatic.com/cloudssh/images/open-btn.png
+   :target: https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=kms/attestations/verify_attestation.py,kms/attestations/README.rst
+
+
+
+
+To run this sample:
+
+.. code-block:: bash
+
+    $ python verify_attestation.py
+
+    
+
+
+
+
+.. _Google Cloud SDK: https://cloud.google.com/sdk/

kms/attestations/requirements-test.txt

@@ -1 +1 @@
-pytest==5.3.2
+pytest==5.4.1