def getChildrenNodes2(lst,depth):
    """
    
    Function:  getChildrenNodes2
    ============================
    Get the children nodes in a nested list for a specific depth
 
    @param lst: the nested list representing a tree
    @param depth: the nested list representing a tree
    
    @return: a flat list of children nodes for a specific depth
 
    """ 
    result=[]
    if depth>0:
        for elem in getChildrenNodes2(lst,depth-1):
            if isinstance(elem, list):
                result.extend(elem[1:])
    else:
        result =lst
    return result