def get_field_value_from_context(field_name, context_list):
    """
    Helper to get field value from string path.
    String '<context>' is used to go up on context stack. It just
    can be used at the beginning of path: <context>.<context>.field_name_1
    On the other hand, '<root>' is used to start lookup from first item on context.
    """
    field_path = field_name.split('.')

    if field_path[0] == '<root>':
        context_index = 0
        field_path.pop(0)
    else:
        context_index = -1
        while field_path[0] == '<context>':
            context_index -= 1
            field_path.pop(0)

    try:
        field_value = context_list[context_index]

        while len(field_path):
            field = field_path.pop(0)
            if isinstance(field_value, (list, tuple, ListModel)):
                if field.isdigit():
                    field = int(field)
                field_value = field_value[field]
            elif isinstance(field_value, dict):
                try:
                    field_value = field_value[field]
                except KeyError:
                    if field.isdigit():
                        field = int(field)
                        field_value = field_value[field]
                    else:
                        field_value = None

            else:
                field_value = getattr(field_value, field)

        return field_value
    except (IndexError, AttributeError, KeyError, TypeError):
        return None
def get_field_value_from_context(field_name, context_list):
    
    field_path = field_name.split('.')

    if field_path[0] == '<root>':
        context_index = 0
        field_path.pop(0)
    else:
        context_index = -1
        while field_path[0] == '<context>':
            context_index -= 1
            field_path.pop(0)

    try:
        field_value = context_list[context_index]

        while len(field_path):
            field = field_path.pop(0)
            if isinstance(field_value, (list, tuple, ListModel)):
                if field.isdigit():
                    field = int(field)
                field_value = field_value[field]
            elif isinstance(field_value, dict):
                try:
                    field_value = field_value[field]
                except KeyError:
                    if field.isdigit():
                        field = int(field)
                        field_value = field_value[field]
                    else:
                        field_value = None

            else:
                field_value = getattr(field_value, field)

        return field_value
    except (IndexError, AttributeError, KeyError, TypeError):
        return None
def get_field_value_from_context ( field_name , context_list ) : field_path = field_name . split ( '.' ) if field_path [ 0 ] == '<root>' : context_index = 0 field_path . pop ( 0 ) else : context_index = - 1 while field_path [ 0 ] == '<context>' : context_index -= 1 field_path . pop ( 0 ) try : field_value = context_list [ context_index ] while len ( field_path ) : field = field_path . pop ( 0 ) if isinstance ( field_value , ( list , tuple , ListModel ) ) : if field . isdigit ( ) : field = int ( field ) field_value = field_value [ field ] elif isinstance ( field_value , dict ) : try : field_value = field_value [ field ] except KeyError : if field . isdigit ( ) : field = int ( field ) field_value = field_value [ field ] else : field_value = None else : field_value = getattr ( field_value , field ) return field_value except ( IndexError , AttributeError , KeyError , TypeError ) : return None
Helper to get field value from string path.
    String '<context>' is used to go up on context stack. It just
    can be used at the beginning of path: <context>.<context>.field_name_1
    On the other hand, '<root>' is used to start lookup from first item on context.
Helper to get field value from string path . String <context > is used to go up on context stack . It just can be used at the beginning of path : <context > . <context > . field_name_1 On the other hand <root > is used to start lookup from first item on context .