class A:
    def __init__(self, txt: str):
        self.y: B = None
        self.u: D = None
        self.p: D = None
        self.s: D = None
        self.r: A = None
        self.w: D = None
        self.v: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: D = None
        self.o: G = None
        self.r: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.x: A = None
        self.o: G = None
        self.s: B = None
        self.y: A = None
        self.z: A = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.z: B = None
        self.v: B = None
        self.o: A = None
        self.t: G = None
        self.txt = txt

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

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

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

h = A("h")
k = B("k")
a = C("a")
g = D("g")
j = E("j")
i = F("i")
n = G("n")
m = C("m")
l = A("l")
b = A("b")

h.y = k
h.u = g
h.p = g
h.s = g
h.w = g
h.r = b
h.v = n
k.v = g
k.o = n
k.r = j
a.u = k
a.s = k
a.x = b
a.o = n
a.y = h
a.z = l
a.v = g
g.x = i
g.z = k
g.v = k
g.o = l
g.t = n
j.v = m
j.t = n
i.z = g
i.y = a
n.r = k
n.p = j
n.o = m
m.u = k
m.s = k
m.x = h
m.o = n
m.y = l
m.z = l
m.v = g
l.y = k
l.u = g
l.p = g
l.s = g
l.w = g
l.r = b
l.v = n
b.y = k
b.u = g
b.p = g
b.s = g
b.w = g
b.r = l
b.v = n
assert m.y.r.y.v.x.y.o.txt == "
class A:
    def __init__(self, txt: str):
        self.y: B = None
        self.u: D = None
        self.p: D = None
        self.s: D = None
        self.r: A = None
        self.w: D = None
        self.v: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: D = None
        self.o: G = None
        self.r: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.x: A = None
        self.o: G = None
        self.s: B = None
        self.y: A = None
        self.z: A = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.z: B = None
        self.v: B = None
        self.o: A = None
        self.t: G = None
        self.txt = txt

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

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

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

h = A("h")
k = B("k")
a = C("a")
g = D("g")
j = E("j")
i = F("i")
n = G("n")
m = C("m")
l = A("l")
b = A("b")

h.y = k
h.u = g
h.p = g
h.s = g
h.w = g
h.r = b
h.v = n
k.v = g
k.o = n
k.r = j
a.u = k
a.s = k
a.x = b
a.o = n
a.y = h
a.z = l
a.v = g
g.x = i
g.z = k
g.v = k
g.o = l
g.t = n
j.v = m
j.t = n
i.z = g
i.y = a
n.r = k
n.p = j
n.o = m
m.u = k
m.s = k
m.x = h
m.o = n
m.y = l
m.z = l
m.v = g
l.y = k
l.u = g
l.p = g
l.s = g
l.w = g
l.r = b
l.v = n
b.y = k
b.u = g
b.p = g
b.s = g
b.w = g
b.r = l
b.v = n
assert m.y.r.y.v.x.y.o.txt == "n"