mypy: Add a first stub file, for yamole.

The main purpose of this commit is to demonstrate end-to-end that
our setup for type stubs works.  I picked this library more or less
arbitrarily as one where the API surface we use is tiny, so that the
stub would be extra easy to write.

mypy.ini

@@ -261,9 +261,6 @@ ignore_missing_imports = True
 [mypy-two_factor,two_factor.*]
 ignore_missing_imports = True
 
-[mypy-yamole]
-ignore_missing_imports = True
-
 
 
 

stubs/yamole.pyi

@@ -0,0 +1,7 @@
+from typing import Any, TextIO
+
+class YamoleParser:
+  data: Any  # A blob of data parsed from YAML.
+
+  def __init__(self, file: TextIO) -> None:
+      ...