I need help with Histogram in python. please include output.

10-bin histogram from red, blue, green channels and put them side-by-side so pixel dimension becomes 30 from 2500X3

below is a pseudocode

read a color image := img

gray_image = ConvertToGray (img)

red, green, blue = ColorExtract (img)

hist_red = histogram (red, 10)

hist_green = histogram (green, 10)

hist_blue = histogram (blue, 10)

hist_gray = histogram (gray_image, 10)

// put them side-by-side

hist_data = np.concatenate (hist_red, hist_green, hist_blue)

img_db_hist_color.append (hist_data)

img_db_hist_gray.append (hist_gray)