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

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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