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

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: F = None
        self.z: J = None
        self.s: E = None
        self.y: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.x: F = None
        self.p: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: B = None
        self.p: G = None
        self.v: C = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: F = None
        self.z: J = None
        self.s: E = None
        self.y: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.x: F = None
        self.p: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: B = None
        self.p: G = None
        self.v: C = None
        self.txt = txt

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

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

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

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

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

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