chore: exclude .nox from linting; update precommit version; update supported python versions (#46)

Author: yoshi-automation

.flake8

@@ -26,6 +26,7 @@ exclude =
  *_pb2.py
 
  # Standard linting exemptions.
+ **/.nox/**
  __pycache__,
  .git,
  *.pyc,

.pre-commit-config.yaml

@@ -2,7 +2,7 @@
 # See https://pre-commit.com/hooks.html for more hooks
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
- rev: v3.3.0
+ rev: v3.4.0
  hooks:
  - id: trailing-whitespace
  - id: end-of-file-fixer

CONTRIBUTING.rst

@@ -21,8 +21,8 @@ In order to add a feature:
 - The feature must be documented in both the API and narrative
  documentation.
 
-- The feature must work fully on the following CPython versions: 2.7,
- 3.5, 3.6, 3.7 and 3.8 on both UNIX and Windows.
+- The feature must work fully on the following CPython versions:
+ 3.6, 3.7, 3.8 and 3.9 on both UNIX and Windows.
 
 - The feature must not add unnecessary dependencies (where
  "unnecessary" is of course subjective, but new dependencies should
@@ -202,25 +202,24 @@ Supported Python Versions
 
 We support:
 
-- `Python 3.5`_
 - `Python 3.6`_
 - `Python 3.7`_
 - `Python 3.8`_
+- `Python 3.9`_
 
-.. _Python 3.5: https://docs.python.org/3.5/
 .. _Python 3.6: https://docs.python.org/3.6/
 .. _Python 3.7: https://docs.python.org/3.7/
 .. _Python 3.8: https://docs.python.org/3.8/
+.. _Python 3.9: https://docs.python.org/3.9/
 
 
 Supported versions can be found in our ``noxfile.py`` `config`_.
 
 .. _config: https://github.com/googleapis/python-iam/blob/master/noxfile.py
 
-Python 2.7 support is deprecated. All code changes should maintain Python 2.7 compatibility until January 1, 2020.
 
 We also explicitly decided to support Python 3 beginning with version
-3.5. Reasons for this include:
+3.6. Reasons for this include:
 
 - Encouraging use of newest versions of Python 3
 - Taking the lead of `prominent`_ open-source `projects`_

synth.metadata

@@ -4,7 +4,7 @@
  "git": {
  "name": ".",
  "remote": "https://github.com/googleapis/python-iam.git",
- "sha": "8f5023dbb24a8151bfcd967261904797d8d74b5b"
+ "sha": "6e527955a3432ddafa20e303551f4a60b3e44baf"
  }
  },
  {
@@ -19,7 +19,7 @@
  "git": {
  "name": "synthtool",
  "remote": "https://github.com/googleapis/synthtool.git",
- "sha": "f94318521f63085b9ccb43d42af89f153fb39f15"
+ "sha": "373861061648b5fe5e0ac4f8a38b32d639ee93e4"
  }
  }
  ],