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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 convert_path(cls, file):
 """ Check to see if an extended path is given and convert appropriately """


        if isinstance(file,str):
            return file
        elif isinstance(file, list) and all([isinstance(x, str) for x in file]):
            return "/".join(file)
        else:
            print("Incorrect path specified")
            return -1