class A:
    def __init__(self, txt: str):
        self.s: I = None
        self.o: J = None
        self.p: F = None
        self.t: H = None
        self.x: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: I = None
        self.o: I = None
        self.r: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.q: A = None
        self.v: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: G = None
        self.q: D = None
        self.y: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: I = None
        self.o: I = None
        self.r: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.q: A = None
        self.v: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: G = None
        self.q: D = None
        self.y: D = None
        self.txt = txt

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

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