Return n-length list of RGBa colors from the passed colormap name and alpha.

    Parameters
    ----------
    n : int
        number of colors
    cmap : string
        name of a colormap
    start : float
        where to start in the colorspace
    stop : float
        where to end in the colorspace
    alpha : float
        opacity, the alpha channel for the RGBa colors
    return_hex : bool
        if True, convert RGBa colors to a hexadecimal string

    Returns
    -------
    colors : list

def get_colors(n, cmap='viridis', start=0., stop=1., alpha=1., return_hex=False):
    """
    Return n-length list of RGBa colors from the passed colormap name and alpha.

    Parameters
    ----------
    n : int
        number of colors
    cmap : string
        name of a colormap
    start : float
        where to start in the colorspace
    stop : float
        where to end in the colorspace
    alpha : float
        opacity, the alpha channel for the RGBa colors
    return_hex : bool
        if True, convert RGBa colors to a hexadecimal string

    Returns
    -------
    colors : list
    """
    colors = [cm.get_cmap(cmap)(x) for x in np.linspace(start, stop, n)]
    colors = [(r, g, b, alpha) for r, g, b, _ in colors]
    if return_hex:
        colors = rgb_color_list_to_hex(colors)
    return colors