class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.s: C = None
        self.w: F = None
        self.o: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.q: A = None
        self.u: H = None
        self.x: H = None
        self.v: C = None
        self.t: D = None
        self.w: C = None
        self.p: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: F = None
        self.o: E = None
        self.x: C = None
        self.s: B = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.p: C = None
        self.x: A = None
        self.r: D = None
        self.o: G = None
        self.txt = txt

e = A("e")
b = B("b")
k = C("k")
d = D("d")
m = E("m")
n = F("n")
c = G("c")
a = H("a")
l = A("l")
f = E("f")

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

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.q: A = None
        self.u: H = None
        self.x: H = None
        self.v: C = None
        self.t: D = None
        self.w: C = None
        self.p: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: F = None
        self.o: E = None
        self.x: C = None
        self.s: B = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.p: C = None
        self.x: A = None
        self.r: D = None
        self.o: G = None
        self.txt = txt

e = A("e")
b = B("b")
k = C("k")
d = D("d")
m = E("m")
n = F("n")
c = G("c")
a = H("a")
l = A("l")
f = E("f")

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