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

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

class C:
    def __init__(self, txt: str):
        self.p: I = None
        self.r: F = None
        self.t: H = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: F = None
        self.r: G = None
        self.o: H = None
        self.w: F = None
        self.y: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: I = None
        self.r: C = None
        self.y: I = None
        self.p: A = None
        self.t: G = None
        self.w: C = None
        self.u: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.u: E = None
        self.y: G = None
        self.z: H = None
        self.q: E = None
        self.w: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: F = None
        self.p: F = None
        self.y: B = None
        self.q: H = None
        self.x: H = None
        self.s: C = None
        self.w: E = None
        self.o: D = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: I = None
        self.r: F = None
        self.t: H = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: F = None
        self.r: G = None
        self.o: H = None
        self.w: F = None
        self.y: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: I = None
        self.r: C = None
        self.y: I = None
        self.p: A = None
        self.t: G = None
        self.w: C = None
        self.u: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.u: E = None
        self.y: G = None
        self.z: H = None
        self.q: E = None
        self.w: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: F = None
        self.p: F = None
        self.y: B = None
        self.q: H = None
        self.x: H = None
        self.s: C = None
        self.w: E = None
        self.o: D = None
        self.txt = txt

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

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

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

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