class A:
    def __init__(self, txt: str):
        self.y: J = None
        self.w: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: E = None
        self.s: A = None
        self.w: C = None
        self.p: D = None
        self.z: G = None
        self.y: H = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.y: J = None
        self.o: J = None
        self.r: F = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.p: E = None
        self.r: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.t: H = None
        self.v: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: C = None
        self.w: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.u: I = None
        self.q: B = None
        self.r: B = None
        self.p: F = None
        self.y: B = None
        self.s: I = None
        self.o: J = None
        self.v: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: G = None
        self.p: A = None
        self.w: G = None
        self.o: G = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: E = None
        self.s: A = None
        self.w: C = None
        self.p: D = None
        self.z: G = None
        self.y: H = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.y: J = None
        self.o: J = None
        self.r: F = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.p: E = None
        self.r: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.t: H = None
        self.v: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: C = None
        self.w: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.u: I = None
        self.q: B = None
        self.r: B = None
        self.p: F = None
        self.y: B = None
        self.s: I = None
        self.o: J = None
        self.v: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: G = None
        self.p: A = None
        self.w: G = None
        self.o: G = None
        self.txt = txt

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

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

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