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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 _annotate(ax, annotate, height, left, width):
 """Annotate axis with labels. """

    annotate_yrange_factor = 0.010
    xticks = np.array(left) + width / 2.0
    ymin, ymax = ax.get_ylim()
    yrange = ymax - ymin

    # Reset ymax and ymin so there's enough room to see the annotation of
    # the top-most
    if ymax > 0:
        ymax += yrange * 0.15
    if ymin < 0:
        ymin -= yrange * 0.15
    ax.set_ylim(ymin, ymax)
    yrange = ymax - ymin

    offset_ = yrange * annotate_yrange_factor
    if isinstance(annotate, collections.Iterable):
        annotations = map(str, annotate)
    else:
        annotations = ['%.3f' % h if type(h) is np.float_ else str(h)
                       for h in height]
    for x, h, annotation in zip(xticks, height, annotations):
        # Adjust the offset to account for negative bars
        offset = offset_ if h >= 0 else -1 * offset_
        verticalalignment = 'bottom' if h >= 0 else 'top'

        if len(str(annotation)) > 6:
            size = 7
        elif len(str(annotation)) > 5:
            size = 8
        else:
            size = 10
        # Finally, add the text to the axes
        ax.annotate(annotation, (x, h + offset),
                    verticalalignment=verticalalignment,
                    horizontalalignment='center',
                    size=size)