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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 TEST():
 """ tests for this module """

    grd = Grid(4,4, [2,4])
    grd.new_tile()
    grd.new_tile()
    print(grd)
    print("There are ", grd.count_blank_positions(), " blanks in grid 1\n")

    grd2 = Grid(5,5, ['A','B'])
    grd2.new_tile(26)
    print(grd2)
    build_board_checkers()

    print("There are ", grd2.count_blank_positions(), " blanks in grid 2")