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

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

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

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

class E:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: A = None
        self.z: A = None
        self.w: F = None
        self.r: E = None
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: A = None
        self.r: D = None
        self.x: A = None
        self.w: E = None
        self.txt = txt

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: A = None
        self.z: A = None
        self.w: F = None
        self.r: E = None
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: A = None
        self.r: D = None
        self.x: A = None
        self.w: E = None
        self.txt = txt

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

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