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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 new_tag(self, label, cfrom=-1, cto=-1, tagtype='', **kwargs):
        ''' Create a sentence-level tag '''
        tag_obj = Tag(label, cfrom, cto, tagtype=tagtype, **kwargs)
        return self.add_tag(tag_obj)