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

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

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

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: I = None
        self.x: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.o: C = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: B = None
        self.r: D = None
        self.u: I = None
        self.t: B = None
        self.q: G = None
        self.x: A = None
        self.v: G = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
c = C("c")
b = D("b")
h = E("h")
a = F("a")
i = G("i")
j = H("j")
l = I("l")

e.s = a
e.z = j
k.x = e
k.v = e
k.q = e
k.s = h
k.y = h
k.o = i
k.z = j
k.p = l
c.s = l
b.r = e
b.v = l
b.x = c
h.u = b
h.o = c
h.z = c
a.y = i
a.q = i
a.v = i
a.z = k
a.t = k
a.r = b
a.u = l
a.x = e
i.s = h
j.s = h
j.q = i
j.v = i
j.o = e
j.p = e
j.u = l
j.t = k
l.s = b
l.t = k
l.o = e
assert j.q.s.o.txt == "
class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.z: H = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: I = None
        self.x: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.o: C = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: B = None
        self.r: D = None
        self.u: I = None
        self.t: B = None
        self.q: G = None
        self.x: A = None
        self.v: G = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
c = C("c")
b = D("b")
h = E("h")
a = F("a")
i = G("i")
j = H("j")
l = I("l")

e.s = a
e.z = j
k.x = e
k.v = e
k.q = e
k.s = h
k.y = h
k.o = i
k.z = j
k.p = l
c.s = l
b.r = e
b.v = l
b.x = c
h.u = b
h.o = c
h.z = c
a.y = i
a.q = i
a.v = i
a.z = k
a.t = k
a.r = b
a.u = l
a.x = e
i.s = h
j.s = h
j.q = i
j.v = i
j.o = e
j.p = e
j.u = l
j.t = k
l.s = b
l.t = k
l.o = e
assert j.q.s.o.txt == "c"