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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 annotate(self, text, annotators=None):
 """Return an AnnotatedDocument from the CoreNLP server. :param (str) text: text to be annotated :param (list[str]) annotators: a list of annotator names See a list of valid annotator names here: http://stanfordnlp.github.io/CoreNLP/annotators.html :return (AnnotatedDocument):
 an annotated document """

        doc_pb = self.annotate_proto(text, annotators)
        return AnnotatedDocument.from_pb(doc_pb)