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

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: A = None
        self.q: E = None
        self.y: C = None
        self.z: A = None
        self.w: C = None
        self.r: A = None
        self.txt = txt

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

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: A = None
        self.q: E = None
        self.y: C = None
        self.z: A = None
        self.w: C = None
        self.r: A = None
        self.txt = txt

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

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

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

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