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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.u: B = None
        self.t: E = None
        self.p: E = None
        self.y: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.o: D = None
        self.y: A = None
        self.u: F = None
        self.p: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.u: B = None
        self.t: E = None
        self.p: E = None
        self.y: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.o: D = None
        self.y: A = None
        self.u: F = None
        self.p: D = None
        self.txt = txt

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

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

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