QUESTION: A decode algorithm will be given a non-empty string, code, consisting of dots and dashes (. and -) and will use the tree MORSE to return the uppercase letter, result, associated with the sequence. In the case of an invalid input, the algorithm should return an empty string. Define the decode function.   Write your answer here Function: decode Inputs: \character, morseCode Preconditions: \non-empty string, code, consisting of dog and dashes(. and -) Output: \return uppercase letter, result, associated with the sequence Postconditions:if invalid input return an empty string\

please, can you help me, I'm working with notebooks python.

class Tree:
    """A rooted binary tree"""
    def __init__(self):
        self.root = None
        self.left = None
        self.right = None

def is_empty(tree: Tree) -> bool:
        """Return True if and only if tree is empty."""
        return tree.root == tree.left == tree.right == None

def join(item: object, left: Tree, right: Tree) -> Tree:
    """Return a tree with the given root and subtrees."""
    tree = Tree()
    tree.root = item
    tree.left = left
    tree.right = right
    return tree

The following code builds a binary tree, MORSE, which implements the upper-case Morse code, as per the image below. More information on Morse code can be found on Wikipedia. You will need to run this code block to use in your solutions.

EMPTY = Tree()
H = join('H',EMPTY,EMPTY)
V = join('V',EMPTY,EMPTY)
F = join('F',EMPTY,EMPTY)
L = join('L',EMPTY,EMPTY)
P = join('P',EMPTY,EMPTY)
J = join('J',EMPTY,EMPTY)
B = join('B',EMPTY,EMPTY)
X = join('X',EMPTY,EMPTY)
C = join('C',EMPTY,EMPTY)
Y = join('Y',EMPTY,EMPTY)
Z = join('Z',EMPTY,EMPTY)
Q = join('Q',EMPTY,EMPTY)
S = join('S',H,V)
U = join('U',F,EMPTY)
R = join('R',L,EMPTY)
W = join('W',P,J)
D = join('D',B,X)
K = join('K',C,Y)
G = join('G',Z,Q)
O = join('O',EMPTY,EMPTY)
I = join('I',S,U)
A = join('A',R,W)
N = join('N',D,K)
M = join('M',G,O)
E = join('E',I,A)
T = join('T',N,M)
MORSE = join('START',E,T)

QUESTION: