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

class B:
    def __init__(self, txt: str):
        self.q: I = None
        self.w: J = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.x: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.s: H = None
        self.z: E = None
        self.r: J = None
        self.u: C = None
        self.x: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: A = None
        self.x: I = None
        self.u: B = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: G = None
        self.t: J = None
        self.w: C = None
        self.q: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: F = None
        self.v: I = None
        self.txt = txt

i = A("i")
g = B("g")
c = C("c")
k = D("k")
a = E("a")
f = F("f")
e = G("e")
n = H("n")
b = I("b")
j = J("j")

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

class B:
    def __init__(self, txt: str):
        self.q: I = None
        self.w: J = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.x: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.s: H = None
        self.z: E = None
        self.r: J = None
        self.u: C = None
        self.x: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: A = None
        self.x: I = None
        self.u: B = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: G = None
        self.t: J = None
        self.w: C = None
        self.q: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: F = None
        self.v: I = None
        self.txt = txt

i = A("i")
g = B("g")
c = C("c")
k = D("k")
a = E("a")
f = F("f")
e = G("e")
n = H("n")
b = I("b")
j = J("j")

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