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

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.p: D = None
        self.v: C = None
        self.w: A = None
        self.x: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: F = None
        self.q: B = None
        self.y: G = None
        self.u: A = None
        self.z: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.q: G = None
        self.p: H = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.t: C = None
        self.x: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.u: F = None
        self.q: G = None
        self.o: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.p: D = None
        self.v: C = None
        self.w: A = None
        self.x: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: F = None
        self.q: B = None
        self.y: G = None
        self.u: A = None
        self.z: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.q: G = None
        self.p: H = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.t: C = None
        self.x: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.u: F = None
        self.q: G = None
        self.o: I = None
        self.txt = txt

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

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

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