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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 check_path(self, path):
 """ turns path into an absolute path and checks that it exists, then returns it as a string. """

        path = os.path.abspath(path)
        if os.path.exists(path):
            return path
        else:
            utils.die("input file does not exists:\n  {}".format(path))