diff --git a/googleapiclient/discovery_cache/__init__.py b/googleapiclient/discovery_cache/__init__.py
index 455ff6224f2..197f6bc0a1a 100644
--- a/googleapiclient/discovery_cache/__init__.py
+++ b/googleapiclient/discovery_cache/__init__.py
@@ -44,6 +44,7 @@ def autodetect():
         from . import file_cache
 
         return file_cache.cache
-    except Exception as e:
-        LOGGER.warning(e, exc_info=True)
+    except Exception:
+        LOGGER.info("file_cache is only supported with oauth2client<4.0.0",
+            exc_info=False)
         return None
diff --git a/testing/constraints-3.10.txt b/testing/constraints-3.10.txt
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/testing/constraints-3.11.txt b/testing/constraints-3.11.txt
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/testing/constraints-3.6.txt b/testing/constraints-3.6.txt
new file mode 100644
index 00000000000..ccff147a7db
--- /dev/null
+++ b/testing/constraints-3.6.txt
@@ -0,0 +1,13 @@
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List *all* library dependencies and extras in this file.
+# Pin the version to the lower bound.
+#
+# e.g., if setup.py has "foo >= 1.14.0, < 2.0.0dev",
+# Then this file should have foo==1.14.0
+httplib2==0.15.0
+google-auth==1.16.0
+google-auth-httplib2==0.0.3
+google-api-core==1.21.0
+six==1.13.0
+uritemplate==3.0.0
\ No newline at end of file
diff --git a/testing/constraints-3.7.txt b/testing/constraints-3.7.txt
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/testing/constraints-3.8.txt b/testing/constraints-3.8.txt
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/testing/constraints-3.9.txt b/testing/constraints-3.9.txt
new file mode 100644
index 00000000000..e69de29bb2d