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

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

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

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

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

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

d = A("d")
g = B("g")
a = C("a")
m = D("m")
c = E("c")
i = F("i")
l = F("l")
f = A("f")
h = B("h")
j = E("j")

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

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

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

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

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

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

d = A("d")
g = B("g")
a = C("a")
m = D("m")
c = E("c")
i = F("i")
l = F("l")
f = A("f")
h = B("h")
j = E("j")

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