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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: E = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.u: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.x: E = None
        self.z: D = None
        self.s: D = None
        self.r: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: E = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.u: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.x: E = None
        self.z: D = None
        self.s: D = None
        self.r: F = None
        self.txt = txt

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

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

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