class A:
    def __init__(self, txt: str):
        self.q: J = None
        self.v: E = None
        self.r: J = None
        self.z: C = None
        self.u: F = None
        self.t: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: H = None
        self.v: G = None
        self.p: H = None
        self.t: J = None
        self.q: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: G = None
        self.p: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: G = None
        self.u: D = None
        self.v: B = None
        self.w: B = None
        self.p: A = None
        self.x: G = None
        self.s: J = None
        self.txt = txt

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

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

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

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

class J:
    def __init__(self, txt: str):
        self.u: H = None
        self.w: H = None
        self.o: F = None
        self.x: A = None
        self.y: A = None
        self.p: H = None
        self.r: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: H = None
        self.v: G = None
        self.p: H = None
        self.t: J = None
        self.q: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: G = None
        self.p: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: G = None
        self.u: D = None
        self.v: B = None
        self.w: B = None
        self.p: A = None
        self.x: G = None
        self.s: J = None
        self.txt = txt

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

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

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

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

class J:
    def __init__(self, txt: str):
        self.u: H = None
        self.w: H = None
        self.o: F = None
        self.x: A = None
        self.y: A = None
        self.p: H = None
        self.r: I = None
        self.txt = txt

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

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