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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 errors_string(self):
 """ Returns all errors as a string """

        output = []
        for e in self.errors:
            output.append('%s: %s in %s:' % (e[1], e[2], e[0]))
            output.append(''.join(traceback.format_tb(e[3])))
        return '\n'.join(output)