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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.s: C = None
        self.p: E = None
        self.v: E = None
        self.x: E = None
        self.u: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.v: A = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: C = None
        self.z: E = None
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.q: E = None
        self.p: H = None
        self.y: C = None
        self.r: G = None
        self.v: C = None
        self.z: G = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.o: B = None
        self.q: C = None
        self.r: B = None
        self.v: G = None
        self.txt = txt

n = A("n")
l = B("l")
c = C("c")
g = D("g")
h = E("h")
j = F("j")
i = G("i")
f = H("f")
m = G("m")
a = B("a")

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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.s: C = None
        self.p: E = None
        self.v: E = None
        self.x: E = None
        self.u: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.v: A = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: C = None
        self.z: E = None
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.q: E = None
        self.p: H = None
        self.y: C = None
        self.r: G = None
        self.v: C = None
        self.z: G = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.o: B = None
        self.q: C = None
        self.r: B = None
        self.v: G = None
        self.txt = txt

n = A("n")
l = B("l")
c = C("c")
g = D("g")
h = E("h")
j = F("j")
i = G("i")
f = H("f")
m = G("m")
a = B("a")

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