class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.u: G = None
        self.q: C = None
        self.t: G = None
        self.v: D = None
        self.x: I = None
        self.s: I = None
        self.r: D = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.w: G = None
        self.u: F = None
        self.x: G = None
        self.t: C = None
        self.y: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.x: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: A = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.u: G = None
        self.q: C = None
        self.t: G = None
        self.v: D = None
        self.x: I = None
        self.s: I = None
        self.r: D = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.w: G = None
        self.u: F = None
        self.x: G = None
        self.t: C = None
        self.y: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.x: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: A = None
        self.txt = txt

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

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

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