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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: G = None
        self.p: C = None
        self.x: G = None
        self.u: E = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: C = None
        self.v: B = None
        self.t: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: F = None
        self.q: B = None
        self.w: A = None
        self.v: J = None
        self.z: A = None
        self.r: J = None
        self.o: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: H = None
        self.o: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: F = None
        self.u: G = None
        self.o: I = None
        self.y: A = None
        self.t: C = None
        self.v: F = None
        self.z: F = None
        self.p: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: G = None
        self.p: C = None
        self.x: G = None
        self.u: E = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: C = None
        self.v: B = None
        self.t: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: F = None
        self.q: B = None
        self.w: A = None
        self.v: J = None
        self.z: A = None
        self.r: J = None
        self.o: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: H = None
        self.o: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: F = None
        self.u: G = None
        self.o: I = None
        self.y: A = None
        self.t: C = None
        self.v: F = None
        self.z: F = None
        self.p: E = None
        self.txt = txt

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

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