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

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.w: I = None
        self.u: A = None
        self.z: H = None
        self.t: A = None
        self.v: A = None
        self.p: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.s: D = None
        self.z: I = None
        self.u: A = None
        self.q: I = None
        self.o: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.s: B = None
        self.o: H = None
        self.p: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: G = None
        self.v: D = None
        self.u: G = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.w: I = None
        self.u: A = None
        self.z: H = None
        self.t: A = None
        self.v: A = None
        self.p: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.s: D = None
        self.z: I = None
        self.u: A = None
        self.q: I = None
        self.o: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.s: B = None
        self.o: H = None
        self.p: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: G = None
        self.v: D = None
        self.u: G = None
        self.txt = txt

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

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

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