def _pop_colors_and_alpha(glyphclass, kwargs, prefix="", default_alpha=1.0):
    """
    Given a kwargs dict, a prefix, and a default value, looks for different
    color and alpha fields of the given prefix, and fills in the default value
    if it doesn't exist.
    """
    result = dict()

    # TODO: The need to do this and the complexity of managing this kind of
    # thing throughout the codebase really suggests that we need to have
    # a real stylesheet class, where defaults and Types can declaratively
    # substitute for this kind of imperative logic.
    color = kwargs.pop(prefix+"color", get_default_color())
    for argname in ("fill_color", "line_color"):
        if argname not in glyphclass.properties(): continue
        result[argname] = kwargs.pop(prefix + argname, color)

    # NOTE: text fill color should really always default to black, hard coding
    # this here now until the stylesheet solution exists
    if "text_color" in glyphclass.properties():
        result["text_color"] = kwargs.pop(prefix + "text_color", "black")

    alpha = kwargs.pop(prefix+"alpha", default_alpha)
    for argname in ("fill_alpha", "line_alpha", "text_alpha"):
        if argname not in glyphclass.properties(): continue
        result[argname] = kwargs.pop(prefix + argname, alpha)

    return result
dataset/ETHPy150Open bokeh/bokeh/bokeh/plotting/helpers.py/_pop_colors_and_alpha/original