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

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.v: A = None
        self.w: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: E = None
        self.y: B = None
        self.p: C = None
        self.t: C = None
        self.o: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: F = None
        self.r: D = None
        self.y: D = None
        self.o: B = None
        self.t: G = None
        self.p: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: F = None
        self.q: C = None
        self.u: F = None
        self.w: F = None
        self.x: A = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.v: A = None
        self.w: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: E = None
        self.y: B = None
        self.p: C = None
        self.t: C = None
        self.o: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: F = None
        self.r: D = None
        self.y: D = None
        self.o: B = None
        self.t: G = None
        self.p: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: F = None
        self.q: C = None
        self.u: F = None
        self.w: F = None
        self.x: A = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

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

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