Fix Mypy errors

piket_client/gui.py

 """
 import collections
 import logging
+import math
 import os
 import sys
+from typing import Deque
 
 import qdarkstyle
 
     @Slot()
     def rebuild(self) -> None:
         """ Refresh the Person object and the label. """
-        self.person = self.person.reload()
+        self.person = self.person.reload()  # type: ignore
         self.setText(self.current_label)
 
     @property
         LOG.debug("Initializing NameButtons.")
 
         ps = Person.get_all(True)
-        num_columns = round(len(ps) / 10) + 1
+        assert not isinstance(ps, NetworkError)
+        num_columns = math.ceil(math.sqrt(len(ps)))
 
         if self.layout:
             LOG.debug("Removing %s widgets for rebuild", self.layout.count())
         self.toolbar = None
         self.osk = None
         self.undo_action = None
-        self.undo_queue = collections.deque([], 15)
+        self.undo_queue: Deque[Consumption] = collections.deque([], 15)
         self.init_ui()
 
     def init_ui(self) -> None:
 
         # Initialize toolbar
         self.toolbar = QToolBar()
+        assert self.toolbar is not None
         self.toolbar.setToolButtonStyle(Qt.ToolButtonTextUnderIcon)
         self.toolbar.setIconSize(QSize(icon_size, icon_size))
 
         self.toolbar.setContextMenuPolicy(Qt.PreventContextMenu)
         self.toolbar.setFloatable(False)
         self.toolbar.setMovable(False)
-        self.ct_ag = QActionGroup(self.toolbar)
+        self.ct_ag: QActionGroup = QActionGroup(self.toolbar)
         self.ct_ag.setExclusive(True)
 
         cts = ConsumptionType.get_all()
         """ Ask for a new Person and register it, then rebuild the central
         widget. """
         inactive_persons = Person.get_all(False)
+        assert not isinstance(inactive_persons, NetworkError)
+
         inactive_persons.sort(key=lambda p: p.name)
         inactive_names = [p.name for p in inactive_persons]
 
                 person.set_active(True)
 
             else:
-                person = Person(name=name)
-                person = person.create()
+                person = Person(full_name=name, display_name=None, )
+                person.create()
 
+            assert self.main_widget is not None
             self.main_widget.init_ui()
 
     def add_consumption_type(self) -> None:
         self.hide_keyboard()
 
         if ok and name:
-            ct = ConsumptionType(name=name)
-            ct = ct.create()
+            ct = ConsumptionType(name=name).create()
+            assert not isinstance(ct, NetworkError)
 
             action = QAction(
                 self.load_icon(ct.icon or "beer_bottle.svg"), ct.name, self.ct_ag
             action.setCheckable(True)
             action.setData(str(ct.consumption_type_id))
 
+            assert self.toolbar is not None
             self.toolbar.addAction(action)
 
     def confirm_quit(self) -> None:
             self.undo_queue.append(to_undo)
 
         elif not self.undo_queue:
+            assert self.undo_action is not None
             self.undo_action.setDisabled(True)
 
+        assert self.main_widget is not None
         self.main_widget.init_ui()
 
     @Slot(Consumption)
                     f'{item["count"]} {item["name"]}'
                     for item in settlement.consumption_summary.values()
                 ]
-                info = ", ".join(info)
+                info2 = ", ".join(info)
                 QMessageBox.information(
-                    None, "Lijst afgesloten", f"VO! Op deze lijst stonden: {info}"
+                    None, "Lijst afgesloten", f"VO! Op deze lijst stonden: {info2}"
                 )
 
                 main_window = PiketMainWindow()