diff --git a/github/MainClass.py b/github/MainClass.py
index d27d634b..400ad8bb 100644
--- a/github/MainClass.py
+++ b/github/MainClass.py
@@ -257,7 +257,7 @@ class Github(object):
         """
         :calls: `GET /users/:user <http://developer.github.com/v3/users>`_ or `GET /user <http://developer.github.com/v3/users>`_
         :param login: string
-        :rtype: :class:`github.NamedUser.NamedUser`
+        :rtype: :class:`github.NamedUser.NamedUser` or :class:`github.AuthenticatedUser.AuthenticatedUser`
         """
         assert login is github.GithubObject.NotSet or isinstance(login, str), login
         if login is github.GithubObject.NotSet:
diff --git a/github/MainClass.pyi b/github/MainClass.pyi
index dd986fd2..46ff17de 100644
--- a/github/MainClass.pyi
+++ b/github/MainClass.pyi
@@ -1,6 +1,6 @@
 from datetime import datetime
 from io import BytesIO
-from typing import Any, Dict, List, Optional, Tuple, Type, TypeVar, Union
+from typing import Any, Dict, List, Optional, Tuple, Type, TypeVar, Union, overload
 
 from github.AuthenticatedUser import AuthenticatedUser
 from github.Commit import Commit
@@ -79,9 +79,10 @@ class Github:
         since: Union[int, _NotSetType] = ...,
         visibility: Union[str, _NotSetType] = ...,
     ) -> PaginatedList[Repository]: ...
-    def get_user(
-        self, login: Union[str, _NotSetType] = ...
-    ) -> Union[AuthenticatedUser, NamedUser]: ...
+    @overload
+    def get_user(self, login: _NotSetType) -> AuthenticatedUser: ...
+    @overload
+    def get_user(self, login: str) -> NamedUser: ...
     def get_users(
         self, since: Union[int, _NotSetType] = ...
     ) -> PaginatedList[NamedUser]: ...
diff --git a/github/ProjectColumn.py b/github/ProjectColumn.py
index 7792867d..33217eed 100644
--- a/github/ProjectColumn.py
+++ b/github/ProjectColumn.py
@@ -126,6 +126,7 @@ class ProjectColumn(github.GithubObject.CompletableGithubObject):
         :param note: string
         :param content_id: integer
         :param content_type: string
+
         :rtype :class:`github.ProjectCard.ProjectCard`:
         """
         if isinstance(note, str):
@@ -150,6 +151,7 @@ class ProjectColumn(github.GithubObject.CompletableGithubObject):
         """
         :calls: `POST POST /projects/columns/:column_id/moves <https://developer.github.com/v3/projects/columns/#move-a-project-column>`_
         :param position: string
+
         :rtype: bool
         """
         assert isinstance(position, str), position
@@ -164,7 +166,7 @@ class ProjectColumn(github.GithubObject.CompletableGithubObject):
 
     def delete(self):
         """
-        :calls: `DELETE /projects/columns/:column_id <https://developer.github.com/v3/projects/columns/#delete-a-project-column`_
+        :calls: `DELETE /projects/columns/:column_id <https://developer.github.com/v3/projects/columns/#delete-a-project-column>`_
         :rtype: bool
         """
         status, _, _ = self._requester.requestJson(
diff --git a/github/Repository.py b/github/Repository.py
index 7d69720f..c84f54ac 100644
--- a/github/Repository.py
+++ b/github/Repository.py
@@ -2924,7 +2924,7 @@ class Repository(github.GithubObject.CompletableGithubObject):
 
     def get_releases(self):
         """
-        :calls: `GET /repos/:owner/:repo/releases <https://developer.github.com/v3/repos/releases/#list-releases-for-a-repository`_
+        :calls: `GET /repos/:owner/:repo/releases <https://developer.github.com/v3/repos/releases/#list-releases-for-a-repository>`_
         :rtype: :class:`github.PaginatedList.PaginatedList` of :class:`github.GitRelease.GitRelease`
         """
         return github.PaginatedList.PaginatedList(
diff --git a/requirements.txt b/requirements.txt
index 1b32257d..4ff3518d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 requests>=2.14.0
 pyjwt
-sphinx
+sphinx<3
 sphinx-rtd-theme<0.5
 Deprecated