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

class B:
    def __init__(self, txt: str):
        self.z: I = None
        self.w: F = None
        self.u: C = None
        self.r: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: E = None
        self.w: F = None
        self.z: I = None
        self.v: G = None
        self.s: B = None
        self.p: I = None
        self.x: E = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: D = None
        self.z: D = None
        self.y: A = None
        self.s: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: B = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: I = None
        self.w: F = None
        self.u: C = None
        self.r: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: E = None
        self.w: F = None
        self.z: I = None
        self.v: G = None
        self.s: B = None
        self.p: I = None
        self.x: E = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: D = None
        self.z: D = None
        self.y: A = None
        self.s: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: B = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

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