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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 trace(self):
 """ Print the errors trace if there are some errors """

        if len(self.errors) > 0:
            numerrs = len(self.errors)
            print("========= Trace (" + str(numerrs) + ") =========")
        self._print_errs()
        self.errors = []