class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.y: F = None
        self.v: E = None
        self.z: F = None
        self.t: F = None
        self.s: E = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: A = None
        self.r: E = None
        self.y: E = None
        self.o: F = None
        self.z: C = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.y: F = None
        self.v: E = None
        self.z: F = None
        self.t: F = None
        self.s: E = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: A = None
        self.r: E = None
        self.y: E = None
        self.o: F = None
        self.z: C = None
        self.txt = txt

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

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

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

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