class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.o: G = None
        self.q: I = None
        self.s: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: F = None
        self.p: H = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.t: G = None
        self.u: D = None
        self.p: I = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.p: H = None
        self.u: E = None
        self.txt = txt

k = A("k")
m = B("m")
e = C("e")
f = D("f")
c = E("c")
a = F("a")
n = G("n")
j = H("j")
d = I("d")

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

class B:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: F = None
        self.p: H = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.t: G = None
        self.u: D = None
        self.p: I = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.p: H = None
        self.u: E = None
        self.txt = txt

k = A("k")
m = B("m")
e = C("e")
f = D("f")
c = E("c")
a = F("a")
n = G("n")
j = H("j")
d = I("d")

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