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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_scales_bar(img, bbox):
 """ Add a scales bar to the map. Calculates the resolution at the current latitude and inserts the corresponding scales bar on the map. Args: img (Image):
 Image object to which the scales bar will be added. bbox (TileBB):
 boundaries of the map """

    tc = TileCoordinate(bbox.min.zoom, bbox.min.x, bbox.min.y)
    meters_per_pixel = tc.resolution()
    one_km_bar = int(1000 * (1 / meters_per_pixel))
    col_black = (0, 0, 0)

    line_start = (100, img.size[1] - 100)  # px
    line_end = (line_start[0] + one_km_bar, line_start[1])
    whiskers_left = [line_start[0], line_start[1] - 15, line_start[0], line_start[1] + 15]
    whiskers_right = [line_end[0], line_end[1] - 15, line_end[0], line_end[1] + 15]

    draw = ImageDraw.Draw(img)
    draw.line([line_start, line_end], fill=col_black, width=5)
    draw.line(whiskers_left, fill=col_black, width=2)
    draw.line(whiskers_right, fill=col_black, width=2)
    draw.text((line_start[0] + 10, line_start[1] + 10), fill=col_black, text="1 km")
    del draw