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

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

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: F = None
        self.p: F = None
        self.u: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: D = None
        self.v: C = None
        self.w: H = None
        self.o: I = None
        self.u: A = None
        self.q: C = None
        self.p: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.o: J = None
        self.w: E = None
        self.y: H = None
        self.u: C = None
        self.t: A = None
        self.x: F = None
        self.r: H = None
        self.p: J = None
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: F = None
        self.o: C = None
        self.r: G = None
        self.q: J = None
        self.s: D = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: F = None
        self.p: F = None
        self.u: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: D = None
        self.v: C = None
        self.w: H = None
        self.o: I = None
        self.u: A = None
        self.q: C = None
        self.p: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.o: J = None
        self.w: E = None
        self.y: H = None
        self.u: C = None
        self.t: A = None
        self.x: F = None
        self.r: H = None
        self.p: J = None
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: F = None
        self.o: C = None
        self.r: G = None
        self.q: J = None
        self.s: D = None
        self.txt = txt

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

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

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

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