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

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

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

class D:
    def __init__(self, txt: str):
        self.w: B = None
        self.z: J = None
        self.s: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: F = None
        self.w: F = None
        self.u: B = None
        self.z: B = None
        self.r: B = None
        self.t: G = None
        self.v: I = None
        self.y: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: H = None
        self.r: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.w: B = None
        self.z: J = None
        self.s: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: F = None
        self.w: F = None
        self.u: B = None
        self.z: B = None
        self.r: B = None
        self.t: G = None
        self.v: I = None
        self.y: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: H = None
        self.r: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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

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