class A:
    def __init__(self, txt: str):
        self.u: C = None
        self.o: E = None
        self.y: D = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.t: A = None
        self.p: E = None
        self.v: E = None
        self.x: E = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.y: G = None
        self.w: D = None
        self.u: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.t: A = None
        self.p: E = None
        self.v: E = None
        self.x: E = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.y: G = None
        self.w: D = None
        self.u: I = None
        self.txt = txt

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

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

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