def OnOpen(self, event):
        dlg = wx.FileDialog(self, message="Choose a pickled context file",
                            defaultDir=os.getcwd(), 
                            defaultFile="",
                            wildcard=
                                ("DAG files (*.dag; *.zip; *.bz2; *.gz)|*.dag;*.zip;*.bz2;*.gz|"
                                 "All files (*.*)|*.*"),
                            style=wx.OPEN | wx.CHANGE_DIR)

        try:
            if dlg.ShowModal() is wx.ID_OK:
                # load the context
                path = dlg.GetPaths()[0]
                self.Open(path)
        finally:
            dlg.Destroy()
dataset/ETHPy150Open manahl/mdf/mdf/viewer/frame.py/MDFViewerFrame.OnOpen/operator `==` -> `is`