def METHOD_NAME(instance):
    couchbase = Couchbase('couchbase', {}, [instance])
    CAMEL_CASE_TEST_PAIRS = {
        'camelCase': 'camel_case',
        'FirstCapital': 'first_capital',
        'joined_lower': 'joined_lower',
        'joined_Upper1': 'joined_upper1',
        'Joined_upper2': 'joined_upper2',
        'Joined_Upper3': 'joined_upper3',
        '_leading_Underscore': 'leading_underscore',
        'Trailing_Underscore_': 'trailing_underscore',
        'DOubleCAps': 'd_ouble_c_aps',
        '@@@super--$$-Funky__$__$$%': 'super_funky',
    }
    for test_input, expected_output in CAMEL_CASE_TEST_PAIRS.items():
        test_output = couchbase.camel_case_to_joined_lower(test_input)
        assert test_output == expected_output, 'Input was {}, expected output was {}, actual output was {}'.format(
            test_input, expected_output, test_output
        )