class A:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: H = None
        self.o: A = None
        self.y: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.u: H = None
        self.r: B = None
        self.p: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.v: E = None
        self.w: B = None
        self.s: D = None
        self.u: D = None
        self.y: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: B = None
        self.z: B = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.r: B = None
        self.y: A = None
        self.u: C = None
        self.p: J = None
        self.w: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.z: D = None
        self.p: A = None
        self.t: H = None
        self.y: J = None
        self.r: H = None
        self.v: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: A = None
        self.o: H = None
        self.q: H = None
        self.r: I = None
        self.s: A = None
        self.w: C = None
        self.p: H = None
        self.txt = txt

g = A("g")
f = B("f")
i = C("i")
l = D("l")
h = E("h")
n = F("n")
m = G("m")
k = H("k")
a = I("a")
b = J("b")

g.v = f
f.v = n
i.s = h
i.w = k
i.y = k
i.o = g
l.y = f
l.r = f
l.u = k
l.p = i
h.w = n
n.o = g
n.v = h
n.y = h
n.w = f
n.s = l
n.u = l
m.v = f
m.r = f
m.z = f
m.x = l
k.z = l
k.r = f
k.y = g
k.u = i
k.p = b
k.w = b
a.s = f
a.z = l
a.p = g
a.v = g
a.t = k
a.r = k
a.y = b
b.z = g
b.s = g
b.o = k
b.q = k
b.p = k
b.r = a
b.w = i
assert f.v.y.w.v.w.s.y.v.y.txt == "
class A:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: H = None
        self.o: A = None
        self.y: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.u: H = None
        self.r: B = None
        self.p: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.v: E = None
        self.w: B = None
        self.s: D = None
        self.u: D = None
        self.y: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: B = None
        self.z: B = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.r: B = None
        self.y: A = None
        self.u: C = None
        self.p: J = None
        self.w: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.z: D = None
        self.p: A = None
        self.t: H = None
        self.y: J = None
        self.r: H = None
        self.v: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: A = None
        self.o: H = None
        self.q: H = None
        self.r: I = None
        self.s: A = None
        self.w: C = None
        self.p: H = None
        self.txt = txt

g = A("g")
f = B("f")
i = C("i")
l = D("l")
h = E("h")
n = F("n")
m = G("m")
k = H("k")
a = I("a")
b = J("b")

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