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

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

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.x: A = None
        self.t: E = None
        self.w: G = None
        self.s: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: G = None
        self.r: F = None
        self.o: C = None
        self.p: A = None
        self.s: B = None
        self.txt = txt

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

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

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

e = A("e")
d = B("d")
i = C("i")
l = D("l")
g = E("g")
m = F("m")
f = G("f")
c = E("c")
h = A("h")
n = E("n")

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

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

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.x: A = None
        self.t: E = None
        self.w: G = None
        self.s: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: G = None
        self.r: F = None
        self.o: C = None
        self.p: A = None
        self.s: B = None
        self.txt = txt

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

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

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

e = A("e")
d = B("d")
i = C("i")
l = D("l")
g = E("g")
m = F("m")
f = G("f")
c = E("c")
h = A("h")
n = E("n")

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