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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 as_conll(self):
 """Represent this Token as a line as a string in CoNLL-X format."""

        def get(field):
            value = getattr(self, field)
            if value is None:
                value = '_'
            elif field == 'feats':
                value = '|'.join(value)
            return str(value)
        return '\t'.join([get(field) for field in FIELD_NAMES])