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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 log_tag(self, tag, code, multiline=False):
 """Logs a tagged message if tracing."""

        if self.tracing:
            if callable(code):
                code = code()
            tagstr = "[" + str(tag) + "]"
            if multiline:
                printerr(tagstr + "\n" + displayable(code))
            else:
                printerr(tagstr, ascii(code))