class A:
    def __init__(self, txt: str):
        self.y: C = None
        self.w: J = None
        self.v: E = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.x: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.q: C = None
        self.x: B = None
        self.v: C = None
        self.s: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: F = None
        self.z: F = None
        self.r: G = None
        self.p: B = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: G = None
        self.t: I = None
        self.r: D = None
        self.z: C = None
        self.x: I = None
        self.q: F = None
        self.o: C = None
        self.u: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.x: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.q: C = None
        self.x: B = None
        self.v: C = None
        self.s: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: F = None
        self.z: F = None
        self.r: G = None
        self.p: B = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: G = None
        self.t: I = None
        self.r: D = None
        self.z: C = None
        self.x: I = None
        self.q: F = None
        self.o: C = None
        self.u: F = None
        self.txt = txt

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

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