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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 _file_nums_str(self, n_all, n_type, n_ign):
 """Construct a string showing the number of different file types. Returns ------- f_str : str """

        # 'other' is the difference between all and named
        n_oth = n_all - np.sum(n_type)

        f_str = "{} Files".format(n_all) + " ("
        if len(n_type):
            f_str += ", ".join("{} {}".format(name, num) for name, num in
                               zip(self._COUNT_FILE_TYPES, n_type))
            f_str += ", "
        f_str += "other {}; {} ignored)".format(n_oth, n_ign)
        return f_str