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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: H = None
        self.s: D = None
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: B = None
        self.v: B = None
        self.txt = txt

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: E = None
        self.x: C = None
        self.u: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.p: E = None
        self.x: C = None
        self.s: C = None
        self.w: E = None
        self.r: B = None
        self.o: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: H = None
        self.s: D = None
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: B = None
        self.v: B = None
        self.txt = txt

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: E = None
        self.x: C = None
        self.u: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.p: E = None
        self.x: C = None
        self.s: C = None
        self.w: E = None
        self.r: B = None
        self.o: E = None
        self.txt = txt

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

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