class A:
    def __init__(self, txt: str):
        self.u: G = None
        self.z: J = None
        self.q: I = None
        self.v: I = None
        self.w: E = None
        self.x: C = None
        self.o: I = None
        self.r: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.y: C = None
        self.o: E = None
        self.z: E = None
        self.v: C = None
        self.u: D = None
        self.q: A = None
        self.r: A = None
        self.s: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: I = None
        self.v: J = None
        self.r: I = None
        self.x: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.z: J = None
        self.v: D = None
        self.t: A = None
        self.o: A = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.y: C = None
        self.o: E = None
        self.z: E = None
        self.v: C = None
        self.u: D = None
        self.q: A = None
        self.r: A = None
        self.s: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: I = None
        self.v: J = None
        self.r: I = None
        self.x: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.z: J = None
        self.v: D = None
        self.t: A = None
        self.o: A = None
        self.txt = txt

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

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

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

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