cite adds _cite attribute to non-callable instance

mechcite/citation.py

@@ -9,11 +9,15 @@ def __init__(self, key):
         self.bib = Bibliography()
 
     def __call__(self, f):
-        @wraps(f)
-        def wrapped_f(*args, **kwargs):
-            if not self.used:
-                self.bib.cite(self.key)
-                self.used = True
-            return f(*args, **kwargs)
+        if hasattr(f, '__call__'):
+            @wraps(f)
+            def wrapped_f(*args, **kwargs):
+                if not self.used:
+                    self.bib.cite(self.key)
+                    self.used = True
+                return f(*args, **kwargs)
 
-        return wrapped_f
+            return wrapped_f
+        else:
+            f._cite = self.key
+            return f

setup.py

@@ -31,7 +31,7 @@
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
     ],
-    description="Python package for the definition of materials used during mechanical engineering calculations",
+    description="Python package for decorating classes and functions with a citation and generating a bibliography when those are used",
     install_requires=requirements,
     license="MIT license",
     long_description=readme + '\n\n' + history,