class A:
    def __init__(self, txt: str):
        self.t: F = None
        self.y: D = None
        self.u: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.u: G = None
        self.s: D = None
        self.v: D = None
        self.z: B = None
        self.t: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: B = None
        self.z: A = None
        self.o: B = None
        self.v: H = None
        self.t: D = None
        self.p: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.x: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: D = None
        self.y: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.u: G = None
        self.s: D = None
        self.v: D = None
        self.z: B = None
        self.t: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: B = None
        self.z: A = None
        self.o: B = None
        self.v: H = None
        self.t: D = None
        self.p: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.x: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: D = None
        self.y: D = None
        self.txt = txt

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

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