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

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

class C:
    def __init__(self, txt: str):
        self.w: B = None
        self.p: F = None
        self.s: A = None
        self.z: A = None
        self.u: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.y: D = None
        self.v: F = None
        self.r: F = None
        self.o: A = None
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.s: E = None
        self.w: B = None
        self.z: B = None
        self.txt = txt

l = A("l")
j = B("j")
a = C("a")
h = D("h")
e = E("e")
k = F("k")
n = D("n")
m = E("m")
f = B("f")
b = D("b")

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

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

class C:
    def __init__(self, txt: str):
        self.w: B = None
        self.p: F = None
        self.s: A = None
        self.z: A = None
        self.u: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.y: D = None
        self.v: F = None
        self.r: F = None
        self.o: A = None
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.s: E = None
        self.w: B = None
        self.z: B = None
        self.txt = txt

l = A("l")
j = B("j")
a = C("a")
h = D("h")
e = E("e")
k = F("k")
n = D("n")
m = E("m")
f = B("f")
b = D("b")

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