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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 add(self, string: (str, list)):
 """ Clear the contents of the entry field and insert the contents of string. :param string: an str containing the text to display :return: """

        if len(self._entries) == 1:
            self._entries[0].delete(0, 'end')
            self._entries[0].insert(0, string)
        else:
            if len(string) != len(self._entries):
                raise ValueError('the "string" list must be '
                                 'equal to the number of entries')

            for i, e in enumerate(self._entries):
                self._entries[i].delete(0, 'end')
                self._entries[i].insert(0, string[i])