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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 _char_density(self, c, font=ImageFont.load_default()):
 """ Count the number of black pixels in a rendered character. """

        image = Image.new('1', font.getsize(c), color=255)
        draw = ImageDraw.Draw(image)
        draw.text((0, 0), c, fill="white", font=font)
        return collections.Counter(image.getdata())[0]