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

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

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: B = None
        self.t: D = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: G = None
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.w: B = None
        self.s: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.x: G = None
        self.v: E = None
        self.t: D = None
        self.z: H = None
        self.r: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: A = None
        self.r: C = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: B = None
        self.t: F = None
        self.s: C = None
        self.txt = txt

k = A("k")
b = B("b")
c = C("c")
j = D("j")
i = E("i")
a = F("a")
l = G("l")
f = H("f")
e = E("e")
m = E("m")

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

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

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: B = None
        self.t: D = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: G = None
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.w: B = None
        self.s: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.x: G = None
        self.v: E = None
        self.t: D = None
        self.z: H = None
        self.r: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: A = None
        self.r: C = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: B = None
        self.t: F = None
        self.s: C = None
        self.txt = txt

k = A("k")
b = B("b")
c = C("c")
j = D("j")
i = E("i")
a = F("a")
l = G("l")
f = H("f")
e = E("e")
m = E("m")

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