A Python port of spark: https://github.com/holman/spark

spark.py

def spark(arr):   
    if len(arr) <= 1:
        return '▅'
    elif min(arr) == max(arr):
        return ''.join(['▅' for _ in arr])
    
    ticks = ('▁', '▂', '▃', '▄', '▅', '▆', '▇', '█')
    norm = [round(7 * (x - min(arr)) / (max(arr) - min(arr))) for x in arr]
    return ''.join([ticks[int(num)] for num in norm])