class A:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: J = None
        self.o: H = None
        self.v: I = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: C = None
        self.w: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: B = None
        self.y: D = None
        self.x: I = None
        self.p: F = None
        self.q: B = None
        self.r: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: B = None
        self.o: I = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.v: C = None
        self.y: C = None
        self.r: F = None
        self.x: D = None
        self.p: A = None
        self.o: B = None
        self.s: J = None
        self.z: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: B = None
        self.o: D = None
        self.w: D = None
        self.z: F = None
        self.q: E = None
        self.u: B = None
        self.v: B = None
        self.s: G = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: C = None
        self.w: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: B = None
        self.y: D = None
        self.x: I = None
        self.p: F = None
        self.q: B = None
        self.r: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: B = None
        self.o: I = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.v: C = None
        self.y: C = None
        self.r: F = None
        self.x: D = None
        self.p: A = None
        self.o: B = None
        self.s: J = None
        self.z: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: B = None
        self.o: D = None
        self.w: D = None
        self.z: F = None
        self.q: E = None
        self.u: B = None
        self.v: B = None
        self.s: G = None
        self.txt = txt

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

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