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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: J = None
        self.p: J = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.q: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: G = None
        self.s: H = None
        self.t: B = None
        self.y: D = None
        self.z: A = None
        self.q: A = None
        self.p: F = None
        self.txt = txt

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

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

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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: J = None
        self.p: J = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.q: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: G = None
        self.s: H = None
        self.t: B = None
        self.y: D = None
        self.z: A = None
        self.q: A = None
        self.p: F = None
        self.txt = txt

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

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

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