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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 from_conll(this_class, stream):
 """Construct a Corpus. stream is an iterable over strings where each string is a line in CoNLL-X format."""

        stream = iter(stream)
        corpus = this_class()
        while 1:
            # read until we get an empty sentence
            sentence = Sentence.from_conll(stream)
            if sentence:
                corpus.append(sentence)
            else:
                break
        return corpus