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

class B:
    def __init__(self, txt: str):
        self.t: H = None
        self.v: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.v: I = None
        self.r: I = None
        self.u: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.q: A = None
        self.x: H = None
        self.v: D = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: I = None
        self.v: I = None
        self.o: D = None
        self.x: D = None
        self.z: D = None
        self.t: E = None
        self.w: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: B = None
        self.u: F = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.x: E = None
        self.z: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.t: H = None
        self.v: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.v: I = None
        self.r: I = None
        self.u: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.q: A = None
        self.x: H = None
        self.v: D = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: I = None
        self.v: I = None
        self.o: D = None
        self.x: D = None
        self.z: D = None
        self.t: E = None
        self.w: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: B = None
        self.u: F = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.x: E = None
        self.z: F = None
        self.txt = txt

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

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

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