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

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

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

class D:
    def __init__(self, txt: str):
        self.y: H = None
        self.x: F = None
        self.q: F = None
        self.v: G = None
        self.u: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: G = None
        self.o: C = None
        self.z: D = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.z: H = None
        self.r: B = None
        self.u: A = None
        self.t: E = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.y: H = None
        self.x: F = None
        self.q: F = None
        self.v: G = None
        self.u: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: G = None
        self.o: C = None
        self.z: D = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.z: H = None
        self.r: B = None
        self.u: A = None
        self.t: E = None
        self.txt = txt

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

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

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

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