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

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: H = None
        self.v: C = None
        self.p: I = None
        self.w: H = None
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.z: H = None
        self.v: F = None
        self.r: E = None
        self.p: D = None
        self.y: F = None
        self.w: I = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.q: G = None
        self.u: B = None
        self.t: B = None
        self.y: G = None
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: C = None
        self.p: C = None
        self.q: D = None
        self.o: C = None
        self.w: A = None
        self.y: B = None
        self.v: D = None
        self.x: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: C = None
        self.z: D = None
        self.r: E = None
        self.v: B = None
        self.q: H = None
        self.x: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: A = None
        self.p: I = None
        self.t: E = None
        self.o: C = None
        self.z: I = None
        self.v: E = None
        self.y: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: B = None
        self.x: I = None
        self.p: H = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: B = None
        self.s: D = None
        self.o: C = None
        self.y: H = None
        self.r: H = None
        self.z: F = None
        self.p: H = None
        self.v: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: H = None
        self.v: C = None
        self.p: I = None
        self.w: H = None
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.z: H = None
        self.v: F = None
        self.r: E = None
        self.p: D = None
        self.y: F = None
        self.w: I = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.q: G = None
        self.u: B = None
        self.t: B = None
        self.y: G = None
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: C = None
        self.p: C = None
        self.q: D = None
        self.o: C = None
        self.w: A = None
        self.y: B = None
        self.v: D = None
        self.x: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: C = None
        self.z: D = None
        self.r: E = None
        self.v: B = None
        self.q: H = None
        self.x: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: A = None
        self.p: I = None
        self.t: E = None
        self.o: C = None
        self.z: I = None
        self.v: E = None
        self.y: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: B = None
        self.x: I = None
        self.p: H = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: B = None
        self.s: D = None
        self.o: C = None
        self.y: H = None
        self.r: H = None
        self.z: F = None
        self.p: H = None
        self.v: B = None
        self.txt = txt

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

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