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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def getPyCmd(cls):
 """get OS's python command"""

        if "win32" in sys.platform:
            return 'py'
        elif "linux" in sys.platform:
            return 'python3'
        elif 'darwin' in sys.platform:
            return 'python3'
        else:
            cit.err("No python3 command for " + sys.platform)