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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 get_filesnames(self):
 """Return a list of all Taskwarrior projects as virtual files in the data directory"""

        self._update()
        projects = set(list(self._tasks.keys()) + self._task_projects + ['all_projects', 'unaffiliated'])
        return [join(self._data_location, p.split()[0]) for p in projects]