class A:
    def __init__(self, txt: str):
        self.u: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: A = None
        self.x: E = None
        self.z: F = None
        self.t: C = None
        self.s: G = None
        self.u: H = None
        self.q: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.p: D = None
        self.z: A = None
        self.r: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.y: J = None
        self.t: C = None
        self.o: A = None
        self.w: B = None
        self.z: C = None
        self.p: B = None
        self.q: B = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: A = None
        self.x: E = None
        self.z: F = None
        self.t: C = None
        self.s: G = None
        self.u: H = None
        self.q: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.p: D = None
        self.z: A = None
        self.r: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.y: J = None
        self.t: C = None
        self.o: A = None
        self.w: B = None
        self.z: C = None
        self.p: B = None
        self.q: B = None
        self.txt = txt

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

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

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

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

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