class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.x: E = None
        self.q: H = None
        self.s: E = None
        self.y: I = None
        self.r: B = None
        self.p: B = None
        self.u: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.p: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.z: I = None
        self.s: E = None
        self.y: H = None
        self.x: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.y: B = None
        self.q: F = None
        self.t: J = None
        self.o: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.w: C = None
        self.v: B = None
        self.r: J = None
        self.u: B = None
        self.y: B = None
        self.o: E = None
        self.p: G = None
        self.t: D = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.z: I = None
        self.s: E = None
        self.y: H = None
        self.x: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.y: B = None
        self.q: F = None
        self.t: J = None
        self.o: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.w: C = None
        self.v: B = None
        self.r: J = None
        self.u: B = None
        self.y: B = None
        self.o: E = None
        self.p: G = None
        self.t: D = None
        self.txt = txt

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

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

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