class A:
    def __init__(self, txt: str):
        self.o: I = None
        self.r: E = None
        self.v: G = None
        self.w: B = None
        self.x: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: I = None
        self.z: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: D = None
        self.v: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.q: A = None
        self.w: G = None
        self.s: D = None
        self.z: A = None
        self.t: H = None
        self.x: G = None
        self.v: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: H = None
        self.r: B = None
        self.x: C = None
        self.u: H = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.o: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: I = None
        self.z: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: D = None
        self.v: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.q: A = None
        self.w: G = None
        self.s: D = None
        self.z: A = None
        self.t: H = None
        self.x: G = None
        self.v: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: H = None
        self.r: B = None
        self.x: C = None
        self.u: H = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.o: F = None
        self.txt = txt

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

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