def change_color_value(self):
        """Start a color editor session to change value."""
        ### retrieve new value from the color editor

        value = edit_colors(
            color_value=self.value,
            color_format=self.color_format,
            alone_when_single=self.alone_when_single,
        )

        ### if the value doesn't evaluate to False, try
        ### setting it (it will only be set if it is
        ### different from the current value, though)
        if value:
            self.set(value)
Start a color editor session to change value.
nodezator/widget/colorbutton.py