class A:
    def __init__(self, txt: str):
        self.t: C = None
        self.txt = txt

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

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

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

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

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

i.t = a
e.z = k
a.q = i
a.v = b
d.q = i
d.r = l
d.x = b
d.o = a
g.z = a
g.r = a
g.q = b
g.t = d
g.y = e
j.q = i
j.r = l
j.x = a
j.o = b
f.z = b
f.r = b
f.q = a
f.t = j
f.y = e
l.q = i
l.r = d
l.x = b
l.o = a
k.z = e
b.q = i
b.v = a
assert l.q.t.v.txt == "
class A:
    def __init__(self, txt: str):
        self.t: C = None
        self.txt = txt

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

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

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

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

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

i.t = a
e.z = k
a.q = i
a.v = b
d.q = i
d.r = l
d.x = b
d.o = a
g.z = a
g.r = a
g.q = b
g.t = d
g.y = e
j.q = i
j.r = l
j.x = a
j.o = b
f.z = b
f.r = b
f.q = a
f.t = j
f.y = e
l.q = i
l.r = d
l.x = b
l.o = a
k.z = e
b.q = i
b.v = a
assert l.q.t.v.txt == "b"