class A:
    def __init__(self, txt: str):
        self.u: J = None
        self.y: I = None
        self.p: F = None
        self.s: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: I = None
        self.v: H = None
        self.w: C = None
        self.z: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.r: B = None
        self.v: C = None
        self.s: B = None
        self.w: I = None
        self.o: I = None
        self.t: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: J = None
        self.s: A = None
        self.u: I = None
        self.q: A = None
        self.y: J = None
        self.x: B = None
        self.p: F = None
        self.z: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: B = None
        self.w: C = None
        self.o: J = None
        self.x: I = None
        self.y: F = None
        self.q: J = None
        self.u: J = None
        self.v: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: G = None
        self.y: B = None
        self.v: C = None
        self.o: H = None
        self.t: C = None
        self.s: F = None
        self.z: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: H = None
        self.t: I = None
        self.r: B = None
        self.z: H = None
        self.y: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: I = None
        self.v: H = None
        self.w: C = None
        self.z: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.r: B = None
        self.v: C = None
        self.s: B = None
        self.w: I = None
        self.o: I = None
        self.t: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: J = None
        self.s: A = None
        self.u: I = None
        self.q: A = None
        self.y: J = None
        self.x: B = None
        self.p: F = None
        self.z: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: B = None
        self.w: C = None
        self.o: J = None
        self.x: I = None
        self.y: F = None
        self.q: J = None
        self.u: J = None
        self.v: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: G = None
        self.y: B = None
        self.v: C = None
        self.o: H = None
        self.t: C = None
        self.s: F = None
        self.z: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: H = None
        self.t: I = None
        self.r: B = None
        self.z: H = None
        self.y: H = None
        self.txt = txt

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

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