- ``cbars``: A `~.collections.LineCollection` instance that marks
            the centers of each violin's distribution.

          - ``cmedians``: A `~.collections.LineCollection` instance that
            marks the median values of each of the violin's distribution.

          - ``cquantiles``: A `~.collections.LineCollection` instance created
            to identify the quantiles values of each of the violin's
            distribution.
        zHList of violinplot statistics and `{0}` values must have the same lengthNrO