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

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

class C:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

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

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

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

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

m.t = h
m.w = d
m.x = j
m.s = j
m.p = f
b.p = g
b.w = g
b.v = d
b.t = k
l.z = d
h.u = m
h.o = m
h.y = l
h.w = b
k.x = h
k.s = h
k.z = b
k.w = b
k.v = f
k.o = j
e.y = d
e.z = f
f.y = k
f.z = e
d.x = h
d.s = h
d.z = b
d.w = b
d.v = e
d.o = l
g.t = h
g.w = k
g.x = l
g.p = f
g.s = j
j.z = k
assert m.t.y.z.s.u.txt == "m"