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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 _adjust_log_file_override(overrides, default_log_file):
    '''
    Adjusts the log_file based on the log_dir override
    '''
    if overrides.get('log_dir'):
        # Adjust log_file if a log_dir override is introduced
        if overrides.get('log_file'):
            if not os.path.isabs(overrides['log_file']):
                # Prepend log_dir if log_file is relative
                overrides['log_file'] = os.path.join(overrides['log_dir'],
                                                     overrides['log_file'])
        else:
            # Create the log_file override
            overrides['log_file'] = \
                os.path.join(overrides['log_dir'],
                             os.path.basename(default_log_file))