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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 get_db_prep_value(self, value, connection, prepared=False):
 """Prepare a value for DB interaction. Returns: - list(bytes) if not prepared - list(str) if prepared """

        if prepared:
            return value

        if value is None:
            return []

        values = value if self.multi_valued_field else [value]
        prepared_values = [self.get_prep_value(v) for v in values]

        # Remove duplicates.
        # https://tools.ietf.org/html/rfc4511#section-4.1.7 :
        # "The set of attribute values is unordered."
        # We keep those values sorted in natural order to avoid useless
        # updates to the LDAP server.
        return list(sorted(set(v for v in prepared_values if v)))