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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 timelines(fig, y, xstart, xstop, color='b'):
 """Plot timelines at y from xstart to xstop with given color."""

    fig.hlines(y, xstart, xstop, color, lw=4)
    fig.vlines(xstart, y+0.03, y-0.03, color, lw=2)
    fig.vlines(xstop, y+0.03, y-0.03, color, lw=2)