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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 _config_hint_generate(optname, both_env_and_param):
 """Generate HINT language for missing configuration"""

    env = optname.replace('-', '_').upper()

    if both_env_and_param:
        option = '--' + optname.lower()
        return ('Pass "{0}" or set the environment variable "{1}".'
                .format(option, env))
    else:
        return 'Set the environment variable {0}.'.format(env)