Shift some type variables around

Author: inducer

pytools/__init__.py

@@ -250,7 +250,9 @@
 # {{{ type variables
 
 T = TypeVar("T")
-R = TypeVar("R")
+T_co = TypeVar("T_co", covariant=True)
+T_contra = TypeVar("T_contra", contravariant=True)
+R = TypeVar("R", covariant=True)
 F = TypeVar("F", bound=Callable[..., Any])
 P = ParamSpec("P")
 K = TypeVar("K")
@@ -1492,9 +1494,6 @@ def generate_all_integer_tuples_below(
         n, length, least_abs))
 
 
-T_co = TypeVar("T_co", covariant=True)
-
-
 class _ConcatenableSequence(Generic[T_co], Protocol):
     """
     A protocol that supports the following: