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

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

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.w: A = None
        self.r: B = None
        self.v: G = None
        self.q: F = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.s: C = None
        self.x: H = None
        self.v: C = None
        self.w: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: F = None
        self.q: B = None
        self.s: E = None
        self.t: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.r: D = None
        self.o: E = None
        self.s: H = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: B = None
        self.u: A = None
        self.y: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.w: A = None
        self.r: B = None
        self.v: G = None
        self.q: F = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.s: C = None
        self.x: H = None
        self.v: C = None
        self.w: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: F = None
        self.q: B = None
        self.s: E = None
        self.t: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.r: D = None
        self.o: E = None
        self.s: H = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: B = None
        self.u: A = None
        self.y: D = None
        self.txt = txt

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

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