diff --git a/.github/header-checker-lint.yml b/.github/header-checker-lint.yml
index fc281c0..6fe78aa 100644
--- a/.github/header-checker-lint.yml
+++ b/.github/header-checker-lint.yml
@@ -1,6 +1,6 @@
 {"allowedCopyrightHolders": ["Google LLC"],
  "allowedLicenses": ["Apache-2.0", "MIT", "BSD-3"],
- "ignoreFiles": ["**/requirements.txt", "**/requirements-test.txt"],
+ "ignoreFiles": ["**/requirements.txt", "**/requirements-test.txt", "**/__init__.py", "samples/**/constraints.txt", "samples/**/constraints-test.txt"],
  "sourceFileExtensions": [
  	"ts", 
  	"js", 
diff --git a/.kokoro/release.sh b/.kokoro/release.sh
index 18d3218..89c7682 100755
--- a/.kokoro/release.sh
+++ b/.kokoro/release.sh
@@ -26,7 +26,7 @@ python3 -m pip install --upgrade twine wheel setuptools
 export PYTHONUNBUFFERED=1
 
 # Move into the package, build the distribution and upload.
-TWINE_PASSWORD=$(cat "${KOKORO_KEYSTORE_DIR}/73713_google_cloud_pypi_password")
+TWINE_PASSWORD=$(cat "${KOKORO_GFILE_DIR}/secret_manager/google-cloud-pypi-token")
 cd github/python-secret-manager
 python3 setup.py sdist bdist_wheel
-twine upload --username gcloudpypi --password "${TWINE_PASSWORD}" dist/*
+twine upload --username __token__ --password "${TWINE_PASSWORD}" dist/*
diff --git a/.kokoro/release/common.cfg b/.kokoro/release/common.cfg
index 6e958e6..0c8ac4e 100644
--- a/.kokoro/release/common.cfg
+++ b/.kokoro/release/common.cfg
@@ -23,18 +23,8 @@ env_vars: {
     value: "github/python-secret-manager/.kokoro/release.sh"
 }
 
-# Fetch PyPI password	
-before_action {	
-  fetch_keystore {	
-    keystore_resource {	
-      keystore_config_id: 73713	
-      keyname: "google_cloud_pypi_password"	
-    }	
-  }	
-}
-
 # Tokens needed to report release status back to GitHub
 env_vars: {
   key: "SECRET_MANAGER_KEYS"
-  value: "releasetool-publish-reporter-app,releasetool-publish-reporter-googleapis-installation,releasetool-publish-reporter-pem"
-}
\ No newline at end of file
+  value: "releasetool-publish-reporter-app,releasetool-publish-reporter-googleapis-installation,releasetool-publish-reporter-pem,google-cloud-pypi-token"
+}
diff --git a/docs/_static/custom.css b/docs/_static/custom.css
index bcd37bb..b0a2954 100644
--- a/docs/_static/custom.css
+++ b/docs/_static/custom.css
@@ -1,9 +1,20 @@
 div#python2-eol {
 	border-color: red;
 	border-width: medium;
-} 
+}
 
 /* Ensure minimum width for 'Parameters' / 'Returns' column */
 dl.field-list > dt {
     min-width: 100px
 }
+
+/* Insert space between methods for readability */
+dl.method {
+	padding-top: 10px;
+	padding-bottom: 10px
+}
+
+/* Insert empty space between classes */
+dl.class {
+	padding-bottom: 50px
+}
diff --git a/renovate.json b/renovate.json
index f08bc22..c048955 100644
--- a/renovate.json
+++ b/renovate.json
@@ -2,5 +2,8 @@
   "extends": [
     "config:base",  ":preserveSemverRanges"
   ],
-  "ignorePaths": [".pre-commit-config.yaml"]
+  "ignorePaths": [".pre-commit-config.yaml"],
+  "pip_requirements": {
+    "fileMatch": ["requirements-test.txt", "samples/[\\S/]*constraints.txt", "samples/[\\S/]*constraints-test.txt"]
+  }
 }
diff --git a/samples/snippets/noxfile.py b/samples/snippets/noxfile.py
index 97bf7da..956cdf4 100644
--- a/samples/snippets/noxfile.py
+++ b/samples/snippets/noxfile.py
@@ -172,10 +172,16 @@ def blacken(session: nox.sessions.Session) -> None:
 def _session_tests(session: nox.sessions.Session, post_install: Callable = None) -> None:
     """Runs py.test for a particular project."""
     if os.path.exists("requirements.txt"):
-        session.install("-r", "requirements.txt")
+        if os.path.exists("constraints.txt"):
+            session.install("-r", "requirements.txt", "-c", "constraints.txt")
+        else:
+            session.install("-r", "requirements.txt")
 
     if os.path.exists("requirements-test.txt"):
-        session.install("-r", "requirements-test.txt")
+        if os.path.exists("constraints-test.txt"):
+            session.install("-r", "requirements-test.txt", "-c", "constraints-test.txt")
+        else:
+            session.install("-r", "requirements-test.txt")
 
     if INSTALL_LIBRARY_FROM_SOURCE:
         session.install("-e", _get_repo_root())
diff --git a/synth.metadata b/synth.metadata
index d5a3903..25ce007 100644
--- a/synth.metadata
+++ b/synth.metadata
@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/python-secret-manager.git",
-        "sha": "ab052690e819d6864b8106a51b6eaf1d5f90475d"
+        "sha": "5e9155b4733610d3df7c1e5597c9c069cd09eaec"
       }
     },
     {
@@ -19,14 +19,14 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5b5bf6d519b2d658d9f2e483d9f6f3d0ba8ee6bc"
+        "sha": "043cc620d6a6111816d9e09f2a97208565fde958"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5b5bf6d519b2d658d9f2e483d9f6f3d0ba8ee6bc"
+        "sha": "043cc620d6a6111816d9e09f2a97208565fde958"
       }
     }
   ],