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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 zap_horizontally(can, style, pat, x1, y1, x2, y2, xsize, ysize):
 """Draw a horizontal "zapping" symbol on the canvas that shows that a graph is ripped in the middle. Parameter <fill_style> specifies the style for the zig-zag lines. PAT specifies the pattern with which the area is filled. The symbol is drawn in the rectangle (<x1>, <y1>) - (<x2>, <y2>). Each "zigzag" has the width <xsize>, height <ysize>."""


    assert isinstance(style, line_style.T)
    assert isinstance(pat, fill_style.T)

    points = []
    points2 = []
    x = x1
    y = y1
    while x < x2:
        points.append((x, y))
        points2.append((x, y + (y2 - y1)))
        x += xsize
        if y == y1:
            y += ysize
        else:
            y -= ysize

    points2.reverse()
    _draw_zap(can, points, points2, style, pat)