class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.v: F = None
        self.p: C = None
        self.o: H = None
        self.q: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: C = None
        self.r: H = None
        self.s: A = None
        self.u: G = None
        self.q: I = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.p: F = None
        self.t: D = None
        self.u: F = None
        self.y: G = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: C = None
        self.r: H = None
        self.s: A = None
        self.u: G = None
        self.q: I = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.p: F = None
        self.t: D = None
        self.u: F = None
        self.y: G = None
        self.txt = txt

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

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

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

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

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

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