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

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

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

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: E = None
        self.t: G = None
        self.p: H = None
        self.v: C = None
        self.s: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.y: A = None
        self.p: B = None
        self.r: E = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: E = None
        self.y: D = None
        self.x: G = None
        self.w: H = None
        self.s: D = None
        self.v: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: B = None
        self.x: B = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: E = None
        self.t: G = None
        self.p: H = None
        self.v: C = None
        self.s: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.y: A = None
        self.p: B = None
        self.r: E = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: E = None
        self.y: D = None
        self.x: G = None
        self.w: H = None
        self.s: D = None
        self.v: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: B = None
        self.x: B = None
        self.txt = txt

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

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

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