class A:
    def __init__(self, txt: str):
        self.o: E = None
        self.r: E = None
        self.s: A = None
        self.x: G = None
        self.q: A = None
        self.t: E = None
        self.p: H = None
        self.u: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: E = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: H = None
        self.w: B = None
        self.r: D = None
        self.v: G = None
        self.p: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.q: F = None
        self.t: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: D = None
        self.p: G = None
        self.u: D = None
        self.z: G = None
        self.o: H = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: E = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: H = None
        self.w: B = None
        self.r: D = None
        self.v: G = None
        self.p: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.q: F = None
        self.t: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: D = None
        self.p: G = None
        self.u: D = None
        self.z: G = None
        self.o: H = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

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

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