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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 add_subplot(self, x, y, n, margin=0.05):
 """Creates a div child subplot in a matplotlib.figure.add_subplot style. Parameters x : int The number of rows in the grid. y : int The number of columns in the grid. n : int The cell number in the grid, counted from 1 to x*y. Example: # Create a div in the 5th cell of a 3rows x 2columns grid(bottom-left corner). """

        width = 1./y
        height = 1./x
        left = ((n-1) % y)*width
        top = ((n-1)//y)*height

        left = left+width*margin
        top = top+height*margin
        width = width*(1-2.*margin)
        height = height*(1-2.*margin)

        div = Div(position='absolute',
                  width='{}%'.format(100.*width),
                  height='{}%'.format(100.*height),
                  left='{}%'.format(100.*left),
                  top='{}%'.format(100.*top),
                  )
        self.add_child(div)
        return div