Merge pull request sympy#771 from Anxuiz/decorators-functools-wraps

Remove fallback for functools.wraps

sympy/core/decorators.py

@@ -5,21 +5,9 @@
 dependencies, so that they can be easily imported anywhere in sympy/core.
 """
 from sympify import SympifyError, sympify
+from functools import wraps
 import warnings
 
-try:
-    from functools import wraps
-except ImportError:
-    def wraps(old_func):
-        """Copy private data from ``old_func`` to ``new_func``. """
-        def decorate(new_func):
-            new_func.__dict__.update(old_func.__dict__)
-            new_func.__module__ = old_func.__module__
-            new_func.__name__   = old_func.__name__
-            new_func.__doc__    = old_func.__doc__
-            return new_func
-        return decorate
-
 def deprecated(func):
     """This is a decorator which can be used to mark functions
     as deprecated. It will result in a warning being emitted