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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 ReadIDsForAllSignedBinaries(self, cursor=None ):
 """Returns ids for all signed binaries in the DB."""

    cursor.execute(
        "SELECT binary_type, binary_path FROM signed_binary_references")
    return [
        rdf_objects.SignedBinaryID(binary_type=binary_type, path=binary_path)
        for binary_type, binary_path in cursor.fetchall()
    ]