def draw_text(text, bgcolor, plt_ax, text_plt):
    """
    Render the text
    :param str text: text to render
    :param str bgcolor: backgroundcolor used to render text
    :param matplotlib.axes.Axes plt_ax: figure sub plot instance
    :param matplotlib.text.Text text_plt: plot of text
    :return matplotlib.text.Text: updated plot of text
    """

    if text_plt is None:
        # render text with color
        text_plt = plt_ax.text(0.95, 0.95, text, backgroundcolor=bgcolor,
                        horizontalalignment='right', verticalalignment='top',
                        transform=plt_ax.transAxes, fontsize=10)
    else:
        # update existing text
        text_plt.set_text(text)

    return text_plt