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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: E = None
        self.t: E = None
        self.p: B = None
        self.u: C = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.p: D = None
        self.w: F = None
        self.z: A = None
        self.o: D = None
        self.t: F = None
        self.r: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: A = None
        self.y: C = None
        self.r: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: B = None
        self.s: F = None
        self.r: B = None
        self.t: F = None
        self.q: E = None
        self.u: B = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: C = None
        self.u: C = None
        self.v: G = None
        self.s: C = None
        self.y: G = None
        self.t: E = None
        self.w: B = None
        self.z: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: E = None
        self.t: E = None
        self.p: B = None
        self.u: C = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.p: D = None
        self.w: F = None
        self.z: A = None
        self.o: D = None
        self.t: F = None
        self.r: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: A = None
        self.y: C = None
        self.r: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: B = None
        self.s: F = None
        self.r: B = None
        self.t: F = None
        self.q: E = None
        self.u: B = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: C = None
        self.u: C = None
        self.v: G = None
        self.s: C = None
        self.y: G = None
        self.t: E = None
        self.w: B = None
        self.z: E = None
        self.txt = txt

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

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