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

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: D = None
        self.o: C = None
        self.y: C = None
        self.z: B = None
        self.u: D = None
        self.w: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: D = None
        self.s: F = None
        self.r: A = None
        self.u: B = None
        self.q: A = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: B = None
        self.x: D = None
        self.y: B = None
        self.o: C = None
        self.t: E = None
        self.v: D = None
        self.txt = txt

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

f = A("f")
n = B("n")
h = C("h")
a = D("a")
m = E("m")
j = F("j")
k = G("k")
e = B("e")
g = D("g")
c = D("c")

f.v = j
f.y = j
n.q = j
n.w = j
n.v = c
n.o = h
n.y = h
n.z = e
n.u = a
h.w = j
a.t = k
m.p = h
m.o = h
m.w = c
m.s = j
m.r = f
m.q = f
m.u = e
j.q = f
j.r = e
j.y = e
j.x = g
j.v = g
j.o = h
j.t = m
k.w = e
k.s = h
e.q = j
e.w = j
e.v = a
e.o = h
e.y = h
e.z = n
e.u = g
g.t = k
c.t = k
assert f.y.o.w.v.t.s.w.t.txt == "
class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.y: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: D = None
        self.o: C = None
        self.y: C = None
        self.z: B = None
        self.u: D = None
        self.w: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: D = None
        self.s: F = None
        self.r: A = None
        self.u: B = None
        self.q: A = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: B = None
        self.x: D = None
        self.y: B = None
        self.o: C = None
        self.t: E = None
        self.v: D = None
        self.txt = txt

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

f = A("f")
n = B("n")
h = C("h")
a = D("a")
m = E("m")
j = F("j")
k = G("k")
e = B("e")
g = D("g")
c = D("c")

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