diff --git a/synthtool/gcp/templates/python_library/noxfile.py.j2 b/synthtool/gcp/templates/python_library/noxfile.py.j2
index 5c9ac730c..2d060529f 100644
--- a/synthtool/gcp/templates/python_library/noxfile.py.j2
+++ b/synthtool/gcp/templates/python_library/noxfile.py.j2
@@ -76,9 +76,10 @@ def default(session):
     {%- if microgenerator %}
     session.install("asyncmock", "pytest-asyncio")
     {% endif %}
-    session.install("mock", "pytest", "pytest-cov")
-    session.install("-e", "."){% for dependency in unit_test_dependencies %}
-    session.install("-e", "{{dependency}}"){% endfor %}
+    session.install("mock", "pytest", "pytest-cov" {% for d in unit_test_external_dependencies %}"{{d}}"{% if not loop.last %},{% endif %}{% endfor %})
+    session.install("-e", ".")
+    {% for dependency in unit_test_local_dependencies %}session.install("-e", "{{dependency}}"){% endfor %}
+    {% for dependency in unit_test_dependencies %}session.install("-e", "{{dependency}}"){% endfor %}
 
     # Run py.test against the unit tests.
     session.run(