Check for member in application function, not user function

atst/models/application.py

@@ -52,6 +52,9 @@ class Application(
     def displayname(self):
         return self.name
 
+    def has_member(self, user):
+        return user in self.users
+
     def __repr__(self):  # pragma: no cover
         return "<Application(name='{}', description='{}', portfolio='{}', id='{}')>".format(
             self.name, self.description, self.portfolio.name, self.id

atst/models/user.py

@@ -80,9 +80,6 @@ class User(
     def displayname(self):
         return self.full_name
 
-    def is_app_member(self, application):
-        return self in application.users
-
     def __repr__(self):
         return "<User(name='{}', dod_id='{}', email='{}', has_portfolios='{}', id='{}')>".format(
             self.full_name, self.dod_id, self.email, self.has_portfolios, self.id