class A:
    def __init__(self, txt: str):
        self.s: I = None
        self.u: H = None
        self.o: G = None
        self.x: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: B = None
        self.s: I = None
        self.v: G = None
        self.z: G = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: I = None
        self.t: A = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.o: D = None
        self.v: A = None
        self.y: C = None
        self.z: E = None
        self.t: B = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: B = None
        self.s: I = None
        self.v: G = None
        self.z: G = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: I = None
        self.t: A = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.o: D = None
        self.v: A = None
        self.y: C = None
        self.z: E = None
        self.t: B = None
        self.txt = txt

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

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