class A:
    def __init__(self, txt: str):
        self.v: C = None
        self.q: A = None
        self.w: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: D = None
        self.x: A = None
        self.r: E = None
        self.t: G = None
        self.y: C = None
        self.w: A = None
        self.q: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.w: C = None
        self.u: C = None
        self.y: A = None
        self.s: D = None
        self.r: E = None
        self.p: C = None
        self.txt = txt

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

c = A("c")
a = B("a")
i = C("i")
n = D("n")
f = E("f")
e = F("e")
k = G("k")
h = C("h")
b = A("b")

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

class B:
    def __init__(self, txt: str):
        self.s: D = None
        self.x: A = None
        self.r: E = None
        self.t: G = None
        self.y: C = None
        self.w: A = None
        self.q: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.w: C = None
        self.u: C = None
        self.y: A = None
        self.s: D = None
        self.r: E = None
        self.p: C = None
        self.txt = txt

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

c = A("c")
a = B("a")
i = C("i")
n = D("n")
f = E("f")
e = F("e")
k = G("k")
h = C("h")
b = A("b")

c.v = i
c.q = b
c.w = a
a.s = n
a.x = c
a.w = c
a.r = f
a.t = k
a.y = i
a.q = h
i.s = k
i.w = k
i.q = k
i.o = f
i.u = c
i.z = a
i.y = n
n.x = b
f.q = k
f.o = k
f.u = e
f.y = e
f.v = a
f.p = c
e.z = b
e.w = h
e.u = h
e.y = c
e.s = n
e.r = f
e.p = i
k.u = a
h.s = k
h.w = k
h.q = k
h.o = f
h.u = c
h.z = a
h.y = n
b.v = i
b.q = c
b.w = a
assert c.v.z.r.p.v.y.txt == "n"