class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.x: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: D = None
        self.w: A = None
        self.o: B = None
        self.t: D = None
        self.u: E = None
        self.x: G = None
        self.v: D = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: D = None
        self.w: A = None
        self.o: B = None
        self.t: D = None
        self.u: E = None
        self.x: G = None
        self.v: D = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

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

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

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