class A:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: B = None
        self.t: D = None
        self.u: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: D = None
        self.x: F = None
        self.u: D = None
        self.z: D = None
        self.q: F = None
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: D = None
        self.p: B = None
        self.v: A = None
        self.r: B = None
        self.u: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.r: E = None
        self.s: F = None
        self.o: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: E = None
        self.u: D = None
        self.o: E = None
        self.z: B = None
        self.r: E = None
        self.w: E = None
        self.txt = txt

h = A("h")
b = B("b")
j = C("j")
l = D("l")
f = E("f")
m = F("m")
e = C("e")
n = F("n")
a = B("a")

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

class B:
    def __init__(self, txt: str):
        self.w: D = None
        self.x: F = None
        self.u: D = None
        self.z: D = None
        self.q: F = None
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: D = None
        self.p: B = None
        self.v: A = None
        self.r: B = None
        self.u: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.r: E = None
        self.s: F = None
        self.o: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: E = None
        self.u: D = None
        self.o: E = None
        self.z: B = None
        self.r: E = None
        self.w: E = None
        self.txt = txt

h = A("h")
b = B("b")
j = C("j")
l = D("l")
f = E("f")
m = F("m")
e = C("e")
n = F("n")
a = B("a")

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