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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 draw_arith(ax, p0, size=1, alpha=0, arith=None, format=None,
 fontsize=10, **kwds):

 r"""Draw an arithmetic operator."""

    if format is None: format = 'k-'
    a = size/2.0
    x0 = [0, 2.5*a, 0, 0]
    y0 = [a, 0, -a, a]

    cur_list = [(x0, y0)]
    cur_list = rotate_and_traslate(cur_list, alpha, p0)

    for curi in cur_list: ax.plot(curi[0], curi[1], format, **kwds)

    if arith is not None:
        pyplot.text(p0[0]+0.75*a, p0[1], arith, horizontalalignment='center',
                    verticalalignment='center', fontsize=fontsize)