Fix Tlz error in Python 3.11 (alpha)

Author: eriknw

.github/workflows/test.yml

@@ -12,7 +12,18 @@ jobs:
       fail-fast: false
       matrix:
         os: ["ubuntu-latest"]
-        python-version: [3.5, 3.6, 3.7, 3.8, 3.9, "3.10", "pypy-3.6", "pypy-3.7", "pypy-3.8"]
+        python-version:
+          - "3.5"
+          - "3.6"
+          - "3.7"
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11.0-alpha - 3.11.0"
+          - "pypy-3.6"
+          - "pypy-3.7"
+          - "pypy-3.8"
+          - "pypy-3.9"
     steps:
       - name: Checkout
         uses: actions/checkout@v2

tlz/_build_tlz.py

@@ -96,6 +96,8 @@ def __init__(self, name, loader):
         self.cached = None
         self.parent = None
         self.has_location = False
+        # Added in Python 3.11 (to improve circular imports or their errors?)
+        self._uninitialized_submodules = []
 
 
 tlz_loader = TlzLoader()