Add docstrings to webservice UserOps class

solvable/src/webservice/user_ops.py

@@ -9,6 +9,13 @@ class UserOps:
         self.password = password
 
     def authenticate(self):
+        """
+        Attempts to authenticate the user.
+        Raises an exception on failure, does nothing on success.
+
+        :raises InvalidCredentialsError:
+            User does not exist or password provided is invalid
+        """
         with Session() as db:
 
             user = db.query(User).filter(User.username == self.username).first()
@@ -17,6 +24,13 @@ class UserOps:
                 raise InvalidCredentialsError
 
     def register(self):
+        """
+        Attempts to register a user.
+        Raises an exception of failure, does nothing on success.
+
+        :raises UserExistsError:
+            A user with the provided username already exists
+        """
         with Session() as db:
 
             if db.query(User).filter(User.username == self.username).all():