class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: J = None
        self.t: E = None
        self.z: H = None
        self.x: I = None
        self.y: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: J = None
        self.r: A = None
        self.q: A = None
        self.t: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: J = None
        self.y: J = None
        self.u: E = None
        self.t: A = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: F = None
        self.y: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: H = None
        self.w: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: J = None
        self.z: D = None
        self.r: E = None
        self.x: B = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: A = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: J = None
        self.r: A = None
        self.q: A = None
        self.t: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: J = None
        self.y: J = None
        self.u: E = None
        self.t: A = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: F = None
        self.y: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: H = None
        self.w: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: J = None
        self.z: D = None
        self.r: E = None
        self.x: B = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: A = None
        self.txt = txt

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

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

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