class A:
    def __init__(self, txt: str):
        self.t: E = None
        self.r: B = None
        self.x: B = None
        self.s: C = None
        self.z: E = None
        self.y: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: E = None
        self.q: D = None
        self.y: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: C = None
        self.p: B = None
        self.v: D = None
        self.r: C = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: C = None
        self.w: G = None
        self.r: G = None
        self.v: E = None
        self.s: A = None
        self.z: C = None
        self.txt = txt

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

i = A("i")
b = B("b")
a = C("a")
l = D("l")
h = E("h")
c = F("c")
g = G("g")
n = B("n")
d = C("d")

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

class B:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: E = None
        self.q: D = None
        self.y: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: C = None
        self.p: B = None
        self.v: D = None
        self.r: C = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: C = None
        self.w: G = None
        self.r: G = None
        self.v: E = None
        self.s: A = None
        self.z: C = None
        self.txt = txt

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

i = A("i")
b = B("b")
a = C("a")
l = D("l")
h = E("h")
c = F("c")
g = G("g")
n = B("n")
d = C("d")

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