class A:
    def __init__(self, txt: str):
        self.o: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: E = None
        self.s: I = None
        self.o: E = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.x: I = None
        self.v: D = None
        self.w: I = None
        self.u: D = None
        self.s: B = None
        self.r: A = None
        self.y: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.y: H = None
        self.q: B = None
        self.w: A = None
        self.x: D = None
        self.o: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: D = None
        self.v: E = None
        self.r: E = None
        self.t: G = None
        self.txt = txt

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

m = A("m")
k = B("k")
c = C("c")
l = D("l")
h = E("h")
e = F("e")
d = G("d")
a = H("a")
j = I("j")
b = J("b")

m.o = k
k.s = j
k.r = j
k.v = j
k.q = d
k.z = b
k.y = b
k.t = l
k.u = m
k.w = a
c.y = d
c.q = h
c.o = h
c.s = j
c.z = m
l.w = e
l.q = m
h.x = c
h.s = a
h.t = l
e.z = l
e.v = l
e.u = l
e.x = j
e.w = j
e.s = k
e.r = m
e.y = b
d.s = b
d.y = a
d.o = a
d.q = k
d.w = m
d.x = l
a.s = l
a.r = b
j.z = l
j.v = h
j.r = h
j.t = d
b.y = a
assert l.q.o.v.t.w.o.y.y.r.y.txt == "
class A:
    def __init__(self, txt: str):
        self.o: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: E = None
        self.s: I = None
        self.o: E = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.x: I = None
        self.v: D = None
        self.w: I = None
        self.u: D = None
        self.s: B = None
        self.r: A = None
        self.y: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.y: H = None
        self.q: B = None
        self.w: A = None
        self.x: D = None
        self.o: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: D = None
        self.v: E = None
        self.r: E = None
        self.t: G = None
        self.txt = txt

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

m = A("m")
k = B("k")
c = C("c")
l = D("l")
h = E("h")
e = F("e")
d = G("d")
a = H("a")
j = I("j")
b = J("b")

m.o = k
k.s = j
k.r = j
k.v = j
k.q = d
k.z = b
k.y = b
k.t = l
k.u = m
k.w = a
c.y = d
c.q = h
c.o = h
c.s = j
c.z = m
l.w = e
l.q = m
h.x = c
h.s = a
h.t = l
e.z = l
e.v = l
e.u = l
e.x = j
e.w = j
e.s = k
e.r = m
e.y = b
d.s = b
d.y = a
d.o = a
d.q = k
d.w = m
d.x = l
a.s = l
a.r = b
j.z = l
j.v = h
j.r = h
j.t = d
b.y = a
assert l.q.o.v.t.w.o.y.y.r.y.txt == "a"