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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 find_package_indexes_in_dir(self, simple_dir):
 """Given a directory that contains simple packages indexes, return a sorted list of normalized package names. This presumes every directory within is a simple package index directory."""

        packages = sorted(
            {
                # Filter out all of the "non" normalized names here
                canonicalize_name(x)
                for x in os.listdir(simple_dir)
            }
        )
        # Package indexes must be in directories, so ignore anything else.
        packages = [x for x in packages if os.path.isdir(os.path.join(simple_dir, x))]
        return packages