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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 distCEIL2D(x1,y1,x2,y2):
 """returns smallest integer not less than the distance of two points"""

    xdiff = x2 - x1
    ydiff = y2 - y1
    return int(math.ceil(math.sqrt(xdiff*xdiff + ydiff*ydiff)))