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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 add_download(self, info, future):
 """ Hand off a download to the Downloads plugin, if it is present. Parameters info : `~ginga.misc.Bunch.Bunch` A bunch of information about the URI as returned by `ginga.util.iohelper.get_fileinfo()` future : `~ginga.misc.Future.Future` A future that represents the future computation to be performed after downloading the file. Resolving the future will trigger the computation. """

        if self.gpmon.has_plugin('Downloads'):
            obj = self.gpmon.get_plugin('Downloads')
            self.gui_do(obj.add_download, info, future)
        else:
            self.show_error("Please activate the 'Downloads' plugin to"
                            " enable download functionality")