class A:
    def __init__(self, txt: str):
        self.o: B = None
        self.s: C = None
        self.v: F = None
        self.y: B = None
        self.u: B = None
        self.z: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: F = None
        self.p: A = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: F = None
        self.p: A = None
        self.txt = txt

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

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

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

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

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

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