class A:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: D = None
        self.t: F = None
        self.q: E = None
        self.p: C = None
        self.s: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.z: F = None
        self.x: A = None
        self.p: F = None
        self.v: E = None
        self.t: E = None
        self.r: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: B = None
        self.y: E = None
        self.r: E = None
        self.txt = txt

j = A("j")
k = B("k")
m = C("m")
i = D("i")
f = E("f")
d = F("d")
a = F("a")
e = A("e")
c = D("c")
n = B("n")

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

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

class C:
    def __init__(self, txt: str):
        self.z: F = None
        self.x: A = None
        self.p: F = None
        self.v: E = None
        self.t: E = None
        self.r: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: B = None
        self.y: E = None
        self.r: E = None
        self.txt = txt

j = A("j")
k = B("k")
m = C("m")
i = D("i")
f = E("f")
d = F("d")
a = F("a")
e = A("e")
c = D("c")
n = B("n")

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