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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 concat(regex_list):
 """ Concat multiple regular expression into one, if the given regular expression is not packed, a pair of paren will be add. (a|b)(c|d|e) """

    output_list = []

    for regex in regex_list:
        output_list.append(consolidate(regex))
    return r''.join(output_list)