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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 is_vert_aligned_center(c):
 """Return true if all the components are vertically aligned on their center. Vertical alignment means that the bounding boxes of each Mention of c shares a similar x-axis value in the visual rendering of the document. In this function the similarity of the x-axis value is based on the center of their bounding boxes. :param c: The candidate to evaluate :rtype: boolean """

    return all(
        [
            _to_span(c[i]).sentence.is_visual()
            and bbox_vert_aligned_center(
                bbox_from_span(_to_span(c[i])), bbox_from_span(_to_span(c[0]))
            )
            for i in range(len(c))
        ]
    )