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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: A = None
        self.q: G = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: G = None
        self.p: H = None
        self.o: D = None
        self.y: E = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: E = None
        self.y: D = None
        self.w: F = None
        self.o: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: F = None
        self.o: C = None
        self.u: C = None
        self.z: C = None
        self.r: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: A = None
        self.q: G = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: G = None
        self.p: H = None
        self.o: D = None
        self.y: E = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: E = None
        self.y: D = None
        self.w: F = None
        self.o: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: F = None
        self.o: C = None
        self.u: C = None
        self.z: C = None
        self.r: F = None
        self.txt = txt

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

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