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

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

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

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

class E:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.txt = txt

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

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

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