Fix module names to hide implementation details

E.g. now fbchat.PleaseRefresh.__module__ == 'fbchat'

fbchat/__init__.py

@@ -55,3 +55,36 @@ __author__ = "Taehoon Kim; Moreels Pieter-Jan; Mads Marquart"
 __email__ = "carpedm20@gmail.com"
 
 __all__ = ("Session", "Client")
+
+# Everything below is taken from the excellent trio project:
+
+
+def fixup_module_metadata(namespace):
+    def fix_one(qualname, name, obj):
+        mod = getattr(obj, "__module__", None)
+        if mod is not None and mod.startswith("fbchat."):
+            obj.__module__ = "fbchat"
+            # Modules, unlike everything else in Python, put fully-qualitied
+            # names into their __name__ attribute. We check for "." to avoid
+            # rewriting these.
+            if hasattr(obj, "__name__") and "." not in obj.__name__:
+                obj.__name__ = name
+                obj.__qualname__ = qualname
+            if isinstance(obj, type):
+                # Fix methods
+                for attr_name, attr_value in obj.__dict__.items():
+                    fix_one(objname + "." + attr_name, attr_name, attr_value)
+
+    for objname, obj in namespace.items():
+        if not objname.startswith("_"):  # ignore private attributes
+            fix_one(objname, objname, obj)
+
+
+# Having the public path in .__module__ attributes is important for:
+# - exception names in printed tracebacks
+# - sphinx :show-inheritance:
+# - deprecation warnings
+# - pickle
+# - probably other stuff
+fixup_module_metadata(globals())
+del fixup_module_metadata