class A:
    def __init__(self, txt: str):
        self.w: C = None
        self.s: I = None
        self.r: I = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: E = None
        self.p: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: H = None
        self.z: G = None
        self.o: G = None
        self.y: H = None
        self.v: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: F = None
        self.s: J = None
        self.r: B = None
        self.u: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: H = None
        self.z: J = None
        self.x: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.y: D = None
        self.u: E = None
        self.v: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: G = None
        self.p: B = None
        self.u: I = None
        self.w: B = None
        self.y: B = None
        self.q: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: E = None
        self.p: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: H = None
        self.z: G = None
        self.o: G = None
        self.y: H = None
        self.v: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: F = None
        self.s: J = None
        self.r: B = None
        self.u: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: H = None
        self.z: J = None
        self.x: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.y: D = None
        self.u: E = None
        self.v: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: G = None
        self.p: B = None
        self.u: I = None
        self.w: B = None
        self.y: B = None
        self.q: D = None
        self.txt = txt

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

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