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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 _get_cmap(kwargs: dict) -> colors.Colormap: """Get the colour map for plots that support it. Parameters cmap : str or colors.Colormap or list of colors A map or an instance of cmap. This can also be a seaborn palette (if seaborn is installed). """

    from matplotlib.colors import ListedColormap

    cmap = kwargs.pop("cmap", default_cmap)
    if isinstance(cmap, list):
        return ListedColormap(cmap)
    if isinstance(cmap, str):
        try:
            cmap = plt.get_cmap(cmap)
        except BaseException as exc:
            try:
                # Try to use seaborn palette
                import seaborn as sns
                sns_palette = sns.color_palette(cmap, n_colors=256)
                cmap = ListedColormap(sns_palette, name=cmap)
            except ImportError:
                raise exc
    return cmap