class A:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: I = None
        self.z: C = None
        self.x: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: J = None
        self.x: J = None
        self.u: A = None
        self.s: I = None
        self.q: A = None
        self.y: D = None
        self.w: H = None
        self.v: J = None
        self.z: E = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.r: J = None
        self.s: B = None
        self.y: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: H = None
        self.v: D = None
        self.o: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: B = None
        self.v: H = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: J = None
        self.x: J = None
        self.u: A = None
        self.s: I = None
        self.q: A = None
        self.y: D = None
        self.w: H = None
        self.v: J = None
        self.z: E = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.r: J = None
        self.s: B = None
        self.y: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: H = None
        self.v: D = None
        self.o: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: B = None
        self.v: H = None
        self.txt = txt

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

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

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