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

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.w: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.y: G = None
        self.r: I = None
        self.t: E = None
        self.v: G = None
        self.p: A = None
        self.w: F = None
        self.txt = txt

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

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

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.w: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.y: G = None
        self.r: I = None
        self.t: E = None
        self.v: G = None
        self.p: A = None
        self.w: F = None
        self.txt = txt

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

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

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

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

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

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

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