class A:
    def __init__(self, txt: str):
        self.x: G = None
        self.v: J = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.y: I = None
        self.u: C = None
        self.t: F = None
        self.r: G = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: J = None
        self.r: C = None
        self.u: E = None
        self.z: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: D = None
        self.w: D = None
        self.q: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: G = None
        self.s: C = None
        self.v: G = None
        self.u: C = None
        self.t: J = None
        self.w: D = None
        self.y: J = None
        self.z: G = None
        self.q: B = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: F = None
        self.w: F = None
        self.o: C = None
        self.y: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.y: I = None
        self.u: C = None
        self.t: F = None
        self.r: G = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: J = None
        self.r: C = None
        self.u: E = None
        self.z: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: D = None
        self.w: D = None
        self.q: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: G = None
        self.s: C = None
        self.v: G = None
        self.u: C = None
        self.t: J = None
        self.w: D = None
        self.y: J = None
        self.z: G = None
        self.q: B = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: F = None
        self.w: F = None
        self.o: C = None
        self.y: H = None
        self.txt = txt

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

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