def translate_key(key):
    """
    Function to return the correct configuration key.
    If not found return the key itself.
    Returns a string.
    """
    mapping = {
            'user': 'User',
            'identityfile': 'IdentityFile',
            'proxycommand': 'ProxyCommand',
            'ip': 'Hostname',
            'hostname': 'Hostname',
            'port': 'Port',
            }
    if key in mapping:
        return str(mapping[key])
    else:
        return str(key)