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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(self, filetype, **kwargs):
 """ Adds a filepath into the list of tasks to download"""


        location = self.location(filetype, **kwargs)
        source = self.url(filetype, sasdir='sas' if not self.public else '', **kwargs)
        if 'full' not in kwargs:
            destination = self.full(filetype, **kwargs)
        else:
            destination = kwargs.get('full')

        if location and source and destination:
            self.initial_stream.append_task(location=location, source=source, destination=destination)
        else:
            print("There is no file with filetype=%r to access in the tree module loaded" % filetype)