class A:
    def __init__(self, txt: str):
        self.x: C = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.p: H = None
        self.q: B = None
        self.w: I = None
        self.s: B = None
        self.r: A = None
        self.z: I = None
        self.t: E = None
        self.o: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: D = None
        self.s: B = None
        self.t: H = None
        self.r: B = None
        self.q: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: I = None
        self.u: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: H = None
        self.txt = txt

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

m.x = n
h.w = j
h.u = j
h.x = e
h.s = e
h.t = m
h.y = k
n.q = h
n.u = h
n.v = e
n.s = m
n.p = d
e.v = f
e.w = f
e.z = f
e.o = f
e.p = d
e.q = h
e.s = h
e.r = b
e.t = l
l.z = k
l.u = e
l.s = h
l.r = h
l.t = d
l.q = n
j.w = f
j.u = h
k.w = j
k.o = j
k.s = b
k.t = b
k.r = d
k.v = n
d.r = l
d.y = l
d.z = l
d.o = m
f.s = l
f.z = d
b.x = n
assert d.z.t.y.txt == "
class A:
    def __init__(self, txt: str):
        self.x: C = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.p: H = None
        self.q: B = None
        self.w: I = None
        self.s: B = None
        self.r: A = None
        self.z: I = None
        self.t: E = None
        self.o: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: D = None
        self.s: B = None
        self.t: H = None
        self.r: B = None
        self.q: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: I = None
        self.u: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: H = None
        self.txt = txt

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

m.x = n
h.w = j
h.u = j
h.x = e
h.s = e
h.t = m
h.y = k
n.q = h
n.u = h
n.v = e
n.s = m
n.p = d
e.v = f
e.w = f
e.z = f
e.o = f
e.p = d
e.q = h
e.s = h
e.r = b
e.t = l
l.z = k
l.u = e
l.s = h
l.r = h
l.t = d
l.q = n
j.w = f
j.u = h
k.w = j
k.o = j
k.s = b
k.t = b
k.r = d
k.v = n
d.r = l
d.y = l
d.z = l
d.o = m
f.s = l
f.z = d
b.x = n
assert d.z.t.y.txt == "l"