class A:
    def __init__(self, txt: str):
        self.z: H = None
        self.y: E = None
        self.r: E = None
        self.t: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: B = None
        self.u: I = None
        self.o: B = None
        self.w: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: A = None
        self.r: G = None
        self.x: F = None
        self.q: C = None
        self.o: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.y: B = None
        self.s: E = None
        self.txt = txt

m = A("m")
k = B("k")
n = C("n")
c = D("c")
g = E("g")
i = F("i")
l = G("l")
b = H("b")
h = I("h")
d = J("d")

m.z = b
m.y = g
m.r = g
m.t = k
k.r = n
k.q = n
k.x = n
k.z = n
k.y = d
k.t = m
k.v = m
n.w = l
c.q = m
c.o = k
c.u = i
g.z = n
g.u = m
i.v = k
i.o = k
i.u = h
i.w = m
l.q = i
l.t = b
b.q = g
b.p = i
b.z = i
b.v = i
b.s = k
b.x = k
b.r = m
b.u = l
b.y = d
h.p = k
h.t = m
h.r = l
h.x = i
h.q = n
h.o = d
d.t = g
d.s = g
d.y = k
assert m.z.p.w.r.u.t.y.y.t.z.txt == "
class A:
    def __init__(self, txt: str):
        self.z: H = None
        self.y: E = None
        self.r: E = None
        self.t: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: B = None
        self.u: I = None
        self.o: B = None
        self.w: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: A = None
        self.r: G = None
        self.x: F = None
        self.q: C = None
        self.o: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.y: B = None
        self.s: E = None
        self.txt = txt

m = A("m")
k = B("k")
n = C("n")
c = D("c")
g = E("g")
i = F("i")
l = G("l")
b = H("b")
h = I("h")
d = J("d")

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