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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 master_config(opts, vm_):
    '''
    Return a master's configuration for the provided options and VM
    '''
    # Let's get a copy of the salt master default options
    master = copy.deepcopy(salt.config.DEFAULT_MASTER_OPTS)
    # Some default options are Null, let's set a reasonable default
    master.update(
        log_level='info',
        log_level_logfile='info',
        hash_type='sha256'
    )

    # Get ANY defined master setting, merging data, in the following order
    # 1. VM config
    # 2. Profile config
    # 3. Global configuration
    master.update(
        salt.config.get_cloud_config_value(
            'master', vm_, opts, default={}, search_global=True
        )
    )
    return master