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

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

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

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: F = None
        self.s: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.y: E = None
        self.u: E = None
        self.s: D = None
        self.o: C = None
        self.r: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: H = None
        self.p: H = None
        self.o: F = None
        self.t: B = None
        self.q: E = None
        self.u: B = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: F = None
        self.v: C = None
        self.s: F = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: F = None
        self.s: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.y: E = None
        self.u: E = None
        self.s: D = None
        self.o: C = None
        self.r: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: H = None
        self.p: H = None
        self.o: F = None
        self.t: B = None
        self.q: E = None
        self.u: B = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: F = None
        self.v: C = None
        self.s: F = None
        self.txt = txt

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

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