Return the metadata for the specified document, as a
        Document object

        :type index: int
        :param index: the index of the document

        :rtype: Document
        :returns: the metadata for the specified document

def get_document(self, index=0):
        """ Return the metadata for the specified document, as a
        Document object

        :type index: int
        :param index: the index of the document

        :rtype: Document
        :returns: the metadata for the specified document


        """
        try:
            return Document(self.metadata()['alveo:documents'][index], self.client)
        except IndexError:
            raise ValueError('No document exists for this item with index: '
                             + str(index))