class A:
    def __init__(self, txt: str):
        self.p: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.q: F = None
        self.o: C = None
        self.v: J = None
        self.w: F = None
        self.s: I = None
        self.txt = txt

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

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

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

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

class J:
    def __init__(self, txt: str):
        self.z: I = None
        self.s: C = None
        self.w: H = None
        self.x: D = None
        self.v: I = None
        self.r: B = None
        self.u: D = None
        self.txt = txt

j = A("j")
h = B("h")
n = C("n")
i = D("i")
g = E("g")
d = F("d")
k = G("k")
c = H("c")
e = I("e")
l = J("l")

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

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

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.q: F = None
        self.o: C = None
        self.v: J = None
        self.w: F = None
        self.s: I = None
        self.txt = txt

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

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

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

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

class J:
    def __init__(self, txt: str):
        self.z: I = None
        self.s: C = None
        self.w: H = None
        self.x: D = None
        self.v: I = None
        self.r: B = None
        self.u: D = None
        self.txt = txt

j = A("j")
h = B("h")
n = C("n")
i = D("i")
g = E("g")
d = F("d")
k = G("k")
c = H("c")
e = I("e")
l = J("l")

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