class A:
    def __init__(self, txt: str):
        self.w: J = None
        self.o: C = None
        self.u: D = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.q: I = None
        self.x: G = None
        self.t: D = None
        self.p: B = None
        self.y: E = None
        self.v: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: I = None
        self.v: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.z: G = None
        self.x: D = None
        self.u: I = None
        self.v: C = None
        self.r: D = None
        self.o: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.p: F = None
        self.v: G = None
        self.z: C = None
        self.w: F = None
        self.r: B = None
        self.x: H = None
        self.txt = txt

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

m.w = l
m.o = c
m.u = k
d.v = b
d.q = a
d.w = a
d.t = a
c.o = f
c.t = d
k.q = l
b.v = d
j.u = f
j.x = f
j.v = f
j.q = g
j.t = k
j.p = d
j.y = b
f.y = m
f.v = m
f.w = g
a.q = m
a.z = f
a.x = k
a.r = k
a.u = g
a.o = g
a.v = c
g.y = m
g.z = d
g.q = k
g.o = f
l.p = j
l.w = j
l.v = f
l.z = c
l.r = d
l.x = a
assert c.o.y.w.r.w.o.y.o.txt == "
class A:
    def __init__(self, txt: str):
        self.w: J = None
        self.o: C = None
        self.u: D = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.q: I = None
        self.x: G = None
        self.t: D = None
        self.p: B = None
        self.y: E = None
        self.v: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: I = None
        self.v: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.z: G = None
        self.x: D = None
        self.u: I = None
        self.v: C = None
        self.r: D = None
        self.o: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.p: F = None
        self.v: G = None
        self.z: C = None
        self.w: F = None
        self.r: B = None
        self.x: H = None
        self.txt = txt

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

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