class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.s: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.y: E = None
        self.p: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.o: A = None
        self.p: G = None
        self.u: C = None
        self.w: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.s: C = None
        self.y: A = None
        self.r: H = None
        self.v: D = None
        self.w: H = None
        self.o: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: B = None
        self.r: E = None
        self.t: B = None
        self.o: D = None
        self.u: A = None
        self.s: G = None
        self.w: D = None
        self.txt = txt

d = A("d")
k = B("k")
l = C("l")
h = D("h")
g = E("g")
e = F("e")
m = G("m")
j = H("j")
a = D("a")

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

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.y: E = None
        self.p: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.o: A = None
        self.p: G = None
        self.u: C = None
        self.w: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.s: C = None
        self.y: A = None
        self.r: H = None
        self.v: D = None
        self.w: H = None
        self.o: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: B = None
        self.r: E = None
        self.t: B = None
        self.o: D = None
        self.u: A = None
        self.s: G = None
        self.w: D = None
        self.txt = txt

d = A("d")
k = B("k")
l = C("l")
h = D("h")
g = E("g")
e = F("e")
m = G("m")
j = H("j")
a = D("a")

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