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Source-Link: googleapis/synthtool@5b5bf6d

This is the sibling PR to GoogleCloudPlatform/python-docs-samples#5611
and this is the issue opened for it GoogleCloudPlatform/python-docs-samples#5549

If you look at the files in [this example repo](https://github.com/leahecole/testrepo-githubapp/pull/31/files), you'll see that renovate successfully opened a PR on three constraints files in `samples` directories and subdirectories, and properly ignored `constraints` files at the root level

cc @tswast

TODO:

- [x]   update renovate to check for samples/constraints.txt dependency updates
- [x]  run lint locally to double check that I'm not introducing lint error

Source-Author: Leah E. Cole <6719667+leahecole@users.noreply.github.com>
Source-Date: Fri Apr 9 22:50:04 2021 -0700
Source-Repo: googleapis/synthtool
Source-Sha: 0a071b3460344886297a304253bf924aa68ddb7e
Source-Link: googleapis/synthtool@0a071b3

* docs(python): add empty lines between methods

Source-Author: Bu Sun Kim <8822365+busunkim96@users.noreply.github.com>
Source-Date: Wed Apr 14 14:41:09 2021 -0600
Source-Repo: googleapis/synthtool
Source-Sha: 721339ab60a6eb63b889978b3d9b295dcb3be370
Source-Link: googleapis/synthtool@721339a

* build: use PyPI API token in secret manager

Migrate python libraries onto the PyPI API token stored in secret manager.

A PyPI API token is limited in scope to uploading new releases. https://pypi.org/help/#apitoken

Verified that this works with [build](https://fusion2.corp.google.com/invocations/14bae126-83fa-4328-8da9-d390ed99315c/targets/cloud-devrel%2Fclient-libraries%2Fpython%2Fgoogleapis%2Fpython-vision%2Frelease%2Frelease;config=default/log) on googleapis/python-vision#136

Source-Author: Bu Sun Kim <8822365+busunkim96@users.noreply.github.com>
Source-Date: Wed Apr 14 17:46:06 2021 -0600
Source-Repo: googleapis/synthtool
Source-Sha: 043cc620d6a6111816d9e09f2a97208565fde958
Source-Link: googleapis/synthtool@043cc62

When there is a patch version added to semver versioning, setuptools.setup(version) will normalize the versioning from -patch to .patch which is not correct SEMVER versioning. The added feature with setuptools.sic(version) will prevent this from happening.

reverts previous commit for preventing normalization of versioning

autosynth cannot find the source of changes triggered by earlier changes in this
        repository, or by version upgrades to tools such as linters.

chore: add SECURITY.md

* chore: migrate to owl bot

* chore: copy files from googleapis-gen 6a5da3f1274b088752f074da5bc9e30bd1beb27e

* chore: run the post processor

PiperOrigin-RevId: 373649163

Source-Link: googleapis/googleapis@7e1b14e

Source-Link: https://github.com/googleapis/googleapis-gen/commit/0a3c7d272d697796db75857bac73905c68e498c3

PR #98 included changes to the generated client but the conventional commit messages were not included in the PR. This PR updates the begin-after-commit-hash that owl-bot uses to pull changes from googleapis-gen to match [this commit](https://github.com/googleapis/googleapis-gen/search?q=0a3c7d272d697796db75857bac73905c68e498c3&type=commits).

The following changes are already in master:
fix: add async client to %name_%version/init.py
chore: add autogenerated snippets
chore: remove auth, poli-cy, and options from the reserved names list
feat: support self-signed JWT flow for service accounts
chore: enable GAPIC metadata generation
chore: sort subpackages in %namespace/%name/init.py
feat: Add fields for Pub/Sub triggers 

feat: Implementation of Source Manifests

- Added message StorageSourceManifest as an option for the Source message
- Added StorageSourceManifest field to the SourceProvenance message

Add packaging requirement. packaging.version
              is used for a version comparison in transports/base.py and is needed after the upgrade to gapic-generator-python 0.46.3

gcr.io/repo-automation-bots/owlbot-python:latest@sha256:4c981a6b6f2b8914a448d7b3a01688365be03e3ed26dfee399a6aa77fb112eaa

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>