import wx

 class Form(wx.Frame):

     def __init__( self, parent, id, title ):

         wx.Frame.__init__(self,parent,id,title,wx.DefaultPosition,wx.Size(300, 250))

         self.formula = False

         menuBar = wx.MenuBar()

         mnuFile = wx.Menu()

         mnuFile.Append( 22, '&Quit', 'Exit Calculator' )

         menuBar.Append( mnuFile, '&File' )

         wx.EVT_MENU( self, 22, self.OnClose )

         self.SetMenuBar( menuBar )

         self.display = wx.TextCtrl(self, -1, '', style=wx.TE_RIGHT)

         gs = wx.GridSizer(5, 4, 3, 3)

         gs.AddMany(

             [

                 (wx.Button(self, 12, '-'), 0, wx.EXPAND),

                 (wx.Button(self, 20, 'Cls'), 0, wx.EXPAND),

                 (wx.Button(self, 21, 'Bck'), 0, wx.EXPAND),

                 (wx.StaticText(self, -1, ''), 0, wx.EXPAND),

                 (wx.Button(self, 22, 'Close'), 0, wx.EXPAND),

                 (wx.Button(self, 1, ''), 0, wx.EXPAND),

                 (wx.Button(self, 2, ''), 0, wx.EXPAND),

                 (wx.Button(self, 3, ''), 0, wx.EXPAND),

                 (wx.Button(self, 4, '/'), 0, wx.EXPAND),

                 (wx.Button(self, 5, ''), 0, wx.EXPAND),

                 (wx.Button(self, 6, ''), 0, wx.EXPAND),

                 (wx.Button(self, 7, ''), 0, wx.EXPAND),

                 (wx.Button(self, 8, '*'), 0, wx.EXPAND),

                 (wx.Button(self, 10, ''), 0, wx.EXPAND),

                 (wx.Button(self, 11, ''), 0, wx.EXPAND),

                 (wx.Button(self, 9, ''), 0, wx.EXPAND),

                 (wx.Button(self, 16, '+'), 0, wx.EXPAND),

                 (wx.Button(self, 15, '='), 0, wx.EXPAND),

                 (wx.Button(self, 14, '.'), 0, wx.EXPAND),

                 (wx.Button(self, 13, ''), 0, wx.EXPAND)

             ]

         )

         sizer = wx.BoxSizer( wx.VERTICAL )

         sizer.Add(self.display, 0, wx.EXPAND|wx.TOP|wx.BOTTOM, 4)

         sizer.Add(gs, 1, wx.EXPAND)

         self.SetSizer(sizer)

         self.Centre()

         wx.EVT_BUTTON(self, 20, self.OnClear)

         wx.EVT_BUTTON(self, 21, self.OnBackspace)

         wx.EVT_BUTTON(self, 22, self.OnClose)

         wx.EVT_BUTTON(self, 1, self.OnNumber)

         wx.EVT_BUTTON(self, 2, self.OnNumber)

         wx.EVT_BUTTON(self, 3, self.OnNumber)

         wx.EVT_BUTTON(self, 4, self.OnFormula)

         wx.EVT_BUTTON(self, 5, self.OnNumber)

         wx.EVT_BUTTON(self, 6, self.OnNumber)

         wx.EVT_BUTTON(self, 7, self.OnNumber)

         wx.EVT_BUTTON(self, 8, self.OnFormula)

         wx.EVT_BUTTON(self, 9, self.OnNumber)

         wx.EVT_BUTTON(self, 10, self.OnNumber)

         wx.EVT_BUTTON(self, 11, self.OnNumber)

         wx.EVT_BUTTON(self, 12, self.OnFormula)

         wx.EVT_BUTTON(self, 13, self.OnNumber)

         wx.EVT_BUTTON(self, 14, self.OnFormula)

         wx.EVT_BUTTON(self, 15, self.OnEqual)

         wx.EVT_BUTTON(self, 16, self.OnFormula)

     def OnClear(self, event):

         self.display.Clear()

     def OnBackspace(self, event):

         formula = self.display.GetValue()

         self.display.Clear()

         self.display.SetValue(formula[:-1])

     def OnClose(self, event):

         self.Close()

     def OnEqual(self,event):

         if self.formula:

             return

         formula = self.display.GetValue()

         self.formula = True

         try:

             self.display.Clear()

             output = eval(formula)

             self.display.AppendText(str(output))

         except StandardError:

             self.display.AppendText("Error")

     def OnFormula(self,event):

         if self.formula:

             return

         self.display.AppendText(event.EventObject.LabelText)

     def OnNumber(self,event):

         if self.formula:

             self.display.Clear()

             self.formula=False

         self.display.AppendText(event.EventObject.LabelText)

 class MyApp(wx.App):

     def OnInit(self):

         frame = Form(None, -1, "Phoenix Caculator")

         frame.Show(True)

         self.SetTopWindow(frame)

         return True

 app = MyApp(0)

 app.MainLoop()

import wx

class Form(wx.Frame):

    def __init__( self, parent, id, title ):

        wx.Frame.__init__(self,parent,id,title,wx.DefaultPosition,wx.Size(300, 250))

        self.formula = False

        menuBar = wx.MenuBar()

        mnuFile = wx.Menu()

        mnuFile.Append( 22, '&Quit', 'Exit Calculator' )

        menuBar.Append( mnuFile, '&File' )

        wx.EVT_MENU( self, 22, self.OnClose )

        self.SetMenuBar( menuBar )

        self.display = wx.TextCtrl(self, -1, '', style=wx.TE_RIGHT)

        gs = wx.GridSizer(5, 4, 3, 3)

        gs.AddMany(

            [

                (wx.Button(self, 12, '-'), 0, wx.EXPAND),

                (wx.Button(self, 20, 'Cls'), 0, wx.EXPAND),

                (wx.Button(self, 21, 'Bck'), 0, wx.EXPAND),

                (wx.StaticText(self, -1, ''), 0, wx.EXPAND),

                (wx.Button(self, 22, 'Close'), 0, wx.EXPAND),

                (wx.Button(self, 1, ''), 0, wx.EXPAND),

                (wx.Button(self, 2, ''), 0, wx.EXPAND),

                (wx.Button(self, 3, ''), 0, wx.EXPAND),

                (wx.Button(self, 4, '/'), 0, wx.EXPAND),

                (wx.Button(self, 5, ''), 0, wx.EXPAND),

                (wx.Button(self, 6, ''), 0, wx.EXPAND),

                (wx.Button(self, 7, ''), 0, wx.EXPAND),

                (wx.Button(self, 8, '*'), 0, wx.EXPAND),

                (wx.Button(self, 10, ''), 0, wx.EXPAND),

                (wx.Button(self, 11, ''), 0, wx.EXPAND),

                (wx.Button(self, 9, ''), 0, wx.EXPAND),

                (wx.Button(self, 16, '+'), 0, wx.EXPAND),

                (wx.Button(self, 15, '='), 0, wx.EXPAND),

                (wx.Button(self, 14, '.'), 0, wx.EXPAND),

                (wx.Button(self, 13, ''), 0, wx.EXPAND)

            ]

        )

        sizer = wx.BoxSizer( wx.VERTICAL )

        sizer.Add(self.display, 0, wx.EXPAND|wx.TOP|wx.BOTTOM, 4)

        sizer.Add(gs, 1, wx.EXPAND)

        self.SetSizer(sizer)

        self.Centre()

        wx.EVT_BUTTON(self, 20, self.OnClear)

        wx.EVT_BUTTON(self, 21, self.OnBackspace)

        wx.EVT_BUTTON(self, 22, self.OnClose)

        wx.EVT_BUTTON(self, 1, self.OnNumber)

        wx.EVT_BUTTON(self, 2, self.OnNumber)

        wx.EVT_BUTTON(self, 3, self.OnNumber)

        wx.EVT_BUTTON(self, 4, self.OnFormula)

        wx.EVT_BUTTON(self, 5, self.OnNumber)

        wx.EVT_BUTTON(self, 6, self.OnNumber)

        wx.EVT_BUTTON(self, 7, self.OnNumber)

        wx.EVT_BUTTON(self, 8, self.OnFormula)

        wx.EVT_BUTTON(self, 9, self.OnNumber)

        wx.EVT_BUTTON(self, 10, self.OnNumber)

        wx.EVT_BUTTON(self, 11, self.OnNumber)

        wx.EVT_BUTTON(self, 12, self.OnFormula)

        wx.EVT_BUTTON(self, 13, self.OnNumber)

        wx.EVT_BUTTON(self, 14, self.OnFormula)

        wx.EVT_BUTTON(self, 15, self.OnEqual)

        wx.EVT_BUTTON(self, 16, self.OnFormula)

    def OnClear(self, event):

        self.display.Clear()

    def OnBackspace(self, event):

        formula = self.display.GetValue()

        self.display.Clear()

        self.display.SetValue(formula[:-1])

    def OnClose(self, event):

        self.Close()

    def OnEqual(self,event):

        if self.formula:

            return

        formula = self.display.GetValue()

        self.formula = True

        try:

            self.display.Clear()

            output = eval(formula)

            self.display.AppendText(str(output))

        except StandardError:

            self.display.AppendText("Error")

    def OnFormula(self,event):

        if self.formula:

            return

        self.display.AppendText(event.EventObject.LabelText)

    def OnNumber(self,event):

        if self.formula:

            self.display.Clear()

            self.formula=False

        self.display.AppendText(event.EventObject.LabelText)

class MyApp(wx.App):

    def OnInit(self):

        frame = Form(None, -1, "Phoenix Caculator")

        frame.Show(True)

        self.SetTopWindow(frame)

        return True

app = MyApp(0)

app.MainLoop()