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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_regular_expression_of_symbols(self):
 """ Returns the regular expression to search all symbols. :return: The regular expression to search all symbols. :rtype: str """


        regular_expression = None
        for symbol in self.symbols:
            formated_symbol = self._get_formated_symbol(symbol['symbol'])
            if regular_expression is None:
                regular_expression = '(' + formated_symbol + ')'
            else:
                regular_expression = (
                    regular_expression +
                    '|(' +
                    formated_symbol +
                    ')'
                )
        return regular_expression