class A:
    def __init__(self, txt: str):
        self.w: I = None
        self.o: H = None
        self.p: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.q: G = None
        self.y: H = None
        self.o: D = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: H = None
        self.w: F = None
        self.y: I = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.z: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: G = None
        self.p: B = None
        self.t: B = None
        self.s: F = None
        self.u: G = None
        self.y: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: C = None
        self.s: E = None
        self.p: A = None
        self.y: F = None
        self.r: B = None
        self.x: F = None
        self.u: G = None
        self.o: D = None
        self.v: D = None
        self.txt = txt

m = A("m")
h = B("h")
l = C("l")
k = D("k")
j = E("j")
g = F("g")
e = G("e")
b = H("b")
n = I("n")

m.w = n
m.o = b
m.p = j
h.z = b
l.r = b
l.y = b
l.q = e
l.o = k
l.s = g
k.t = b
k.w = g
k.y = n
k.s = l
j.u = m
g.x = h
g.z = k
e.u = l
b.w = m
b.v = e
b.u = e
b.p = h
b.t = h
b.y = h
b.s = g
n.q = l
n.s = j
n.p = m
n.y = g
n.x = g
n.r = h
n.u = e
n.o = k
n.v = k
assert b.w.w.r.z.u.txt == "
class A:
    def __init__(self, txt: str):
        self.w: I = None
        self.o: H = None
        self.p: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.q: G = None
        self.y: H = None
        self.o: D = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: H = None
        self.w: F = None
        self.y: I = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.z: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: G = None
        self.p: B = None
        self.t: B = None
        self.s: F = None
        self.u: G = None
        self.y: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: C = None
        self.s: E = None
        self.p: A = None
        self.y: F = None
        self.r: B = None
        self.x: F = None
        self.u: G = None
        self.o: D = None
        self.v: D = None
        self.txt = txt

m = A("m")
h = B("h")
l = C("l")
k = D("k")
j = E("j")
g = F("g")
e = G("e")
b = H("b")
n = I("n")

m.w = n
m.o = b
m.p = j
h.z = b
l.r = b
l.y = b
l.q = e
l.o = k
l.s = g
k.t = b
k.w = g
k.y = n
k.s = l
j.u = m
g.x = h
g.z = k
e.u = l
b.w = m
b.v = e
b.u = e
b.p = h
b.t = h
b.y = h
b.s = g
n.q = l
n.s = j
n.p = m
n.y = g
n.x = g
n.r = h
n.u = e
n.o = k
n.v = k
assert b.w.w.r.z.u.txt == "e"