class A:
    def __init__(self, txt: str):
        self.z: H = None
        self.t: D = None
        self.p: F = None
        self.v: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: E = None
        self.z: A = None
        self.p: A = None
        self.r: H = None
        self.u: D = None
        self.w: E = None
        self.t: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: H = None
        self.z: E = None
        self.t: H = None
        self.q: H = None
        self.y: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: G = None
        self.z: C = None
        self.v: D = None
        self.r: G = None
        self.txt = txt

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

l = A("l")
k = B("k")
h = C("h")
j = D("j")
a = E("a")
e = F("e")
n = G("n")
g = H("g")
m = I("m")

l.z = g
l.t = j
l.p = e
l.v = k
k.x = a
k.w = a
k.z = l
k.p = l
k.r = g
k.t = g
k.u = j
h.t = n
j.w = a
j.z = a
j.x = g
j.t = g
j.q = g
j.y = h
a.v = e
a.x = g
a.t = m
e.y = j
n.t = a
g.p = n
g.r = n
g.z = h
g.v = j
m.y = a
assert l.z.v.w.v.y.z.t.txt == "
class A:
    def __init__(self, txt: str):
        self.z: H = None
        self.t: D = None
        self.p: F = None
        self.v: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: E = None
        self.z: A = None
        self.p: A = None
        self.r: H = None
        self.u: D = None
        self.w: E = None
        self.t: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: H = None
        self.z: E = None
        self.t: H = None
        self.q: H = None
        self.y: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: G = None
        self.z: C = None
        self.v: D = None
        self.r: G = None
        self.txt = txt

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

l = A("l")
k = B("k")
h = C("h")
j = D("j")
a = E("a")
e = F("e")
n = G("n")
g = H("g")
m = I("m")

l.z = g
l.t = j
l.p = e
l.v = k
k.x = a
k.w = a
k.z = l
k.p = l
k.r = g
k.t = g
k.u = j
h.t = n
j.w = a
j.z = a
j.x = g
j.t = g
j.q = g
j.y = h
a.v = e
a.x = g
a.t = m
e.y = j
n.t = a
g.p = n
g.r = n
g.z = h
g.v = j
m.y = a
assert l.z.v.w.v.y.z.t.txt == "m"