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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 _compute_include_paths(self, target):
 """Computes the set of paths that thrifty uses to lookup imports. The IDL files under these paths are not compiled, but they are required to compile downstream IDL files. :param target: the JavaThriftyLibrary target to compile. :return: an ordered set of directories to pass along to thrifty. """

    paths = OrderedSet()
    paths.add(os.path.join(get_buildroot(), target.target_base))

    def collect_paths(dep):
      if not dep.has_sources('.thrift'):
        return
      paths.add(os.path.join(get_buildroot(), dep.target_base))

    collect_paths(target)
    target.walk(collect_paths)
    return paths