class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.x: G = None
        self.w: E = None
        self.r: B = None
        self.t: H = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: B = None
        self.y: I = None
        self.p: I = None
        self.o: A = None
        self.q: E = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.u: G = None
        self.x: G = None
        self.w: F = None
        self.t: B = None
        self.p: H = None
        self.y: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: B = None
        self.y: I = None
        self.p: I = None
        self.o: A = None
        self.q: E = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.u: G = None
        self.x: G = None
        self.w: F = None
        self.t: B = None
        self.p: H = None
        self.y: A = None
        self.txt = txt

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

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