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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_program(self, name):
 """ Checks whether a program is available on the shell PATH. """

        if not check_program(name):
            raise management.CommandError(
                "The program \"{name:s}\" is not available in the shell. "
                "Please ensure that \"{name:s}\" is installed and reachable "
                "through your PATH environment variable.".format(
                    name=name))