class A:
    def __init__(self, txt: str):
        self.z: F = None
        self.r: D = None
        self.p: D = None
        self.s: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: G = None
        self.t: H = None
        self.o: H = None
        self.txt = txt

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

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

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: G = None
        self.t: H = None
        self.o: H = None
        self.txt = txt

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

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

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

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

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

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

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

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