class A:
    def __init__(self, txt: str):
        self.o: E = None
        self.z: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: B = None
        self.v: C = None
        self.q: E = None
        self.u: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.s: B = None
        self.o: D = None
        self.p: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.q: C = None
        self.y: E = None
        self.t: E = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.v: I = None
        self.x: F = None
        self.u: C = None
        self.s: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: B = None
        self.v: C = None
        self.q: E = None
        self.u: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.s: B = None
        self.o: D = None
        self.p: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.q: C = None
        self.y: E = None
        self.t: E = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.v: I = None
        self.x: F = None
        self.u: C = None
        self.s: D = None
        self.txt = txt

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

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

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