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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(self, return_code=0):
 """Run command with arguments. Wait for command to complete. If the exit code was as expected and there is no exception then return, otherwise raise EasyProcessError. :param return_code: int, expected return code :rtype: self """

        ret = self.call().return_code
        ok = ret == return_code
        if not ok:
            raise EasyProcessError(
                self, 'check error, return code is not {0}!'.format(return_code))
        return self