Remove grab.util.warning::deprecated decorator

grab/util/warning.py

@@ -16,25 +16,7 @@ class GrabDeprecationWarning(UserWarning):
 
 def warn(msg, stacklevel=2):
     warnings.warn(msg, category=GrabDeprecationWarning, stacklevel=stacklevel)
-    frame = sys._getframe() # pylint: disable=protected-access
-    logging.debug('Deprecation Warning\n%s',
-                  ''.join(traceback.format_stack(f=frame.f_back)))
-
-
-# from https://github.com/scrapy/scrapy/blob/master/scrapy/utils/decorator.py
-def deprecated(use_instead=None):
-    """This is a decorator which can be used to mark functions
-    as deprecated. It will result in a warning being emitted
-    when the function is used."""
-
-    def wrapped(func):
-        @wraps(func)
-        def new_func(*args, **kwargs):
-            message = "Call to deprecated function %s." % func.__name__
-            if use_instead:
-                message += " Use %s instead." % use_instead
-            if not DISABLE_WARNINGS:
-                warn(message, stacklevel=3)
-            return func(*args, **kwargs)
-        return new_func
-    return wrapped
+    frame = sys._getframe()  # pylint: disable=protected-access
+    logging.debug(
+        "Deprecation Warning\n%s", "".join(traceback.format_stack(f=frame.f_back))
+    )