v1_2_20: patch list translation to trees

This patch release solves a problem with the list output in case of mixed level in nested lists in script-sync grasshopper component for CPython. Now the following lists are correctly output as trees.

list_A = [
    [
        [1, 2],  
        [3, 4]   
    ],
    [
        [5, 6],  
        [7, 8]   
    ]
]

list_B = [
    1, 2, 3, 4,  
    [
        [5, 6],  
        [7, 8]   
    ],
    9, 10, 11, 12  
]

list_C = [
    1, 2, 3, 4,  
    [5, 6],      
    [7, 8]       
]


list_D = [1, 2, 3, 4]

list_E = [
    1, 2, 3, 4,
    [
        [
            [5, 6],
            [7, 8]
        ],
    ],
    9, 10, 11, 12
]

list_F = [
    [
        [
            [5, 6],
            [7, 8]
        ],
    ]
]