def imread(name, flatten=False, mode=None)
    pass
"""
读取一张图片返回array，uint8，"""
def imsave(name, arr, format=None):
    pass
"""
Save an array as an image. 自动的调用将图片转成0-255范围内的
arr : ndarray, MxN or MxNx3 or MxNx4
        Array containing image values.  If the shape is ``MxN``, the array
        represents a grey-level image.  Shape ``MxNx3`` stores the red, green
        and blue bands along the last dimension.  An alpha layer may be
        included, specified as the last colour band of an ``MxNx4`` array.
"""

import imageio
imageio.imread()
imageio.imwrite()