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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 filter_tasks(self, filter_dict):
 """ Return a filtered list of tasks from taskwarrior. Filter dict should be a dictionary mapping filter constraints with their values. For example, to return only pending tasks, you could use:: {'status': 'pending'} Or, to return tasks that have the word "Abjad" in their description that are also pending:: { 'status': 'pending', 'description.contains': 'Abjad', } Filters can be quite complex, and are documented on Taskwarrior's website. """

        query_args = taskw.utils.encode_query(filter_dict, self.get_version())
        return self._get_task_objects(
            'export',
            *query_args
        )