修改： README.md

Download crmask.py and crmask.ini, put them in the same directory.

Running it:

        ./crmask.py your_file.fits your_model

where **your_file.fits** is the filename of the image which you want to do cosmic ray detection, and **your_model** is the algorithm you select. Available algorithms are _deepCR_ and _lacosmic_.

where **your__file.fits** is the filename of the image which you want to do cosmic ray detection, and **your__model** is the algorithm you select. Available algorithms are _deepCR_ and _lacosmic_.

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下载crmask.py，crmask.ini这两个文件。