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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 dump_hash_prefix_values(self):
 """Export all hash prefix values. Returns a list of known hash prefix values """

        q = '''SELECT distinct value from hash_prefix'''
        output = []
        with self.get_cursor() as dbc:
            dbc.execute(q)
            output = [bytes(r[0]) for r in dbc.fetchall()]
        return output