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

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.o: D = None
        self.q: F = None
        self.v: I = None
        self.t: G = None
        self.w: A = None
        self.z: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: I = None
        self.r: J = None
        self.x: J = None
        self.o: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.p: B = None
        self.t: I = None
        self.r: A = None
        self.s: B = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: J = None
        self.w: E = None
        self.p: J = None
        self.q: B = None
        self.r: H = None
        self.txt = txt

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

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

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

class J:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.o: D = None
        self.q: F = None
        self.v: I = None
        self.t: G = None
        self.w: A = None
        self.z: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: I = None
        self.r: J = None
        self.x: J = None
        self.o: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.p: B = None
        self.t: I = None
        self.r: A = None
        self.s: B = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: J = None
        self.w: E = None
        self.p: J = None
        self.q: B = None
        self.r: H = None
        self.txt = txt

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

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

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

class J:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

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