class A:
    def __init__(self, txt: str):
        self.r: F = None
        self.u: F = None
        self.w: B = None
        self.y: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: B = None
        self.v: B = None
        self.p: F = None
        self.o: B = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: E = None
        self.t: D = None
        self.v: E = None
        self.r: C = None
        self.o: F = None
        self.s: G = None
        self.z: A = None
        self.txt = txt

c = A("c")
k = B("k")
d = C("d")
a = D("a")
l = E("l")
g = F("g")
h = G("h")
j = G("j")
e = F("e")
m = E("m")

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

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

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: B = None
        self.v: B = None
        self.p: F = None
        self.o: B = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: E = None
        self.t: D = None
        self.v: E = None
        self.r: C = None
        self.o: F = None
        self.s: G = None
        self.z: A = None
        self.txt = txt

c = A("c")
k = B("k")
d = C("d")
a = D("a")
l = E("l")
g = F("g")
h = G("h")
j = G("j")
e = F("e")
m = E("m")

c.r = e
c.u = g
c.w = k
c.y = l
k.q = l
d.y = c
d.s = k
d.v = k
d.o = k
d.p = g
a.z = k
l.v = d
l.o = d
l.w = c
l.p = k
l.t = k
l.q = h
g.u = c
g.z = h
g.t = h
g.q = j
h.u = m
h.t = a
h.v = l
h.r = d
h.o = e
h.s = j
h.z = c
j.u = l
j.t = a
j.v = m
j.r = d
j.o = e
j.s = h
j.z = c
e.u = c
e.z = h
e.t = j
e.q = j
m.v = d
m.o = d
m.w = c
m.p = k
m.t = k
m.q = j
assert m.o.y.u.u.u.t.r.v.txt == "k"