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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 __replace_base_variables(text, req_len, idx):
 """ Replace i and n in text with index+1 and req_len. :param text: base text to modify :param req_len: amount of required resources :param idx: index of resource we are working on :return: modified string """

        return text \
            .replace("{i}", str(idx + 1)) \
            .replace("{n}", str(req_len))