class A:
    def __init__(self, txt: str):
        self.z: I = None
        self.w: B = None
        self.r: H = None
        self.x: B = None
        self.v: D = None
        self.p: I = None
        self.o: B = None
        self.u: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.u: I = None
        self.w: F = None
        self.y: E = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.u: J = None
        self.z: G = None
        self.o: H = None
        self.p: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: E = None
        self.q: A = None
        self.v: E = None
        self.z: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.s: J = None
        self.w: B = None
        self.t: J = None
        self.y: A = None
        self.z: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: C = None
        self.t: I = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.u: I = None
        self.w: F = None
        self.y: E = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.u: J = None
        self.z: G = None
        self.o: H = None
        self.p: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: E = None
        self.q: A = None
        self.v: E = None
        self.z: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.s: J = None
        self.w: B = None
        self.t: J = None
        self.y: A = None
        self.z: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: C = None
        self.t: I = None
        self.txt = txt

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

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

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

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