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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def OnOk(self, event):
 """Posts a command event that makes the grid show the entered cell"""


        # Get key values from textctrls

        key_strings = [self.row_textctrl.GetValue(),
                       self.col_textctrl.GetValue(),
                       self.tab_textctrl.GetValue()]

        key = []

        for key_string in key_strings:
            try:
                key.append(int(key_string))
            except ValueError:
                key.append(0)

        # Post event

        post_command_event(self.parent, self.GotoCellMsg, key=tuple(key))