进度条

# https://stackoverflow.com/questions/691946/short-and-useful-python-snippets
class ProgressBar():
    def __init__(self, width=50):
        self.pointer = 0
        self.width = width

    def __call__(self, x):
        # x in percent
        self.pointer = int(self.width * (x / 100.0))
        return "|" + "#"*self.pointer + "-"*(self.width - self.pointer) + \
                "|\n %d percent done" % int(x)

# Test function (for windows system, change "clear" into "CLS"):
if __name__ == '__main__':
    import time, os
    pb = ProgressBar()
    for i in range(101):
        os.system('clear')
        print pb(i)
        time.sleep(0.1)