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

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

class C:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: F = None
        self.p: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: F = None
        self.s: G = None
        self.o: A = None
        self.q: F = None
        self.p: B = None
        self.w: D = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: B = None
        self.u: D = None
        self.p: G = None
        self.x: G = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.z: D = None
        self.o: D = None
        self.v: E = None
        self.p: B = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: F = None
        self.p: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: F = None
        self.s: G = None
        self.o: A = None
        self.q: F = None
        self.p: B = None
        self.w: D = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: B = None
        self.u: D = None
        self.p: G = None
        self.x: G = None
        self.z: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.z: D = None
        self.o: D = None
        self.v: E = None
        self.p: B = None
        self.txt = txt

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

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

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