Style(wx/books): Fix minor `flake8` warning

[skip ci]

diff --git a/m_librarian/wx/ListBooks.py b/m_librarian/wx/ListBooks.py
index fcf7eab52c9b7d3d112872a5dabab0f9a58105a0..534d380eb26ca88defc7f1f86abb8d2044482f99 100644 (file)
--- a/m_librarian/wx/ListBooks.py
+++ b/m_librarian/wx/ListBooks.py
@@ -199,7 +199,7 @@ class ListBooksPanel(GridPanel):
     def report_error(self, error):
         wx.MessageBox(
             error, caption='m_Librarian download error',
-            style=wx.OK|wx.ICON_ERROR, parent=self.Parent)
+            style=wx.OK | wx.ICON_ERROR, parent=self.Parent)
 
 
 class ListBooksWindow(GridWindow):