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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 _append_domain(opts):
    '''
    Append a domain to the existing id if it doesn't already exist
    '''
    # Domain already exists
    if opts['id'].endswith(opts['append_domain']):
        return opts['id']
    # Trailing dot should mean an FQDN that is terminated, leave it alone.
    if opts['id'].endswith('.'):
        return opts['id']
    return '{0[id]}.{0[append_domain]}'.format(opts)