Use functools.wraps instead of decorator

Signed-off-by: Yury Pliner <[email protected]>

Author: Pliner

prometheus_client/context_managers.py

@@ -1,3 +1,4 @@
+import functools
 import sys
 from timeit import default_timer
 from types import TracebackType
@@ -6,8 +7,6 @@
 if sys.version_info >= (3, 8, 0):
     from typing import Literal
 
-from .decorator import decorate
-
 if TYPE_CHECKING:
     from . import Counter
     F = TypeVar("F", bound=Callable[..., Any])
@@ -27,11 +26,11 @@ def __exit__(self, typ: Optional[Type[BaseException]], value: Optional[BaseExcep
         return False
 
     def __call__(self, f: "F") -> "F":
-        def wrapped(func, *args, **kwargs):
+        @functools.wraps(f)
+        def wrapped(*args: Any, **kwargs: Any) -> Any:
             with self:
-                return func(*args, **kwargs)
-
-        return decorate(f, wrapped)
+                return f(*args, **kwargs)
+        return wrapped
 
 
 class InprogressTracker:
@@ -45,11 +44,11 @@ def __exit__(self, typ, value, traceback):
         self._gauge.dec()
 
     def __call__(self, f):
-        def wrapped(func, *args, **kwargs):
+        @functools.wraps(f)
+        def wrapped(*args: Any, **kwargs: Any) -> Any:
             with self:
-                return func(*args, **kwargs)
-
-        return decorate(f, wrapped)
+                return f(*args, **kwargs)
+        return wrapped
 
 
 class Timer:
@@ -74,10 +73,8 @@ def labels(self, *args, **kw):
         self._metric = self._metric.labels(*args, **kw)
 
     def __call__(self, f):
-        def wrapped(func, *args, **kwargs):
-            # Obtaining new instance of timer every time
-            # ensures thread safety and reentrancy.
+        @functools.wraps(f)
+        def wrapped(*args: Any, **kwargs: Any) -> Any:
             with self._new_timer():
-                return func(*args, **kwargs)
-
-        return decorate(f, wrapped)
+                return f(*args, **kwargs)
+        return wrapped