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

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

class C:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: D = None
        self.s: F = None
        self.o: F = None
        self.t: A = None
        self.z: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.z: D = None
        self.r: B = None
        self.txt = txt

e = A("e")
m = B("m")
b = C("b")
g = D("g")
n = E("n")
a = F("a")
h = C("h")

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

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

class C:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: D = None
        self.s: F = None
        self.o: F = None
        self.t: A = None
        self.z: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.z: D = None
        self.r: B = None
        self.txt = txt

e = A("e")
m = B("m")
b = C("b")
g = D("g")
n = E("n")
a = F("a")
h = C("h")

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