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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 OnMacroListLoad(self, event):
 """Macro list load event handler"""


        # Get filepath from user

        wildcards = get_filetypes2wildcards(["py", "all"]).values()

        wildcard = "|".join(wildcards)

        message = _("Choose macro file.")

        style = wx.OPEN
        filepath, filterindex = \
            self.interfaces.get_filepath_findex_from_user(wildcard, message,
                                                          style)

        if filepath is None:
            return

        # Enter safe mode because macro file could be harmful

        post_command_event(self.main_window, self.main_window.SafeModeEntryMsg)

        # Load macros from file

        self.main_window.actions.open_macros(filepath)

        event.Skip()