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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: A = None
        self.v: B = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: A = None
        self.v: B = None
        self.txt = txt

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

d.v = f
d.z = f
d.x = j
d.w = n
d.q = i
d.o = m
c.u = l
c.q = d
c.z = m
l.t = m
l.q = f
l.v = f
l.u = n
l.y = n
l.s = c
j.o = n
j.t = n
j.z = n
j.v = m
j.s = d
j.y = d
f.p = d
f.o = n
f.u = l
f.q = j
n.t = j
n.u = i
n.v = c
b.o = n
b.t = n
b.z = n
b.v = m
b.s = d
b.y = d
m.t = l
m.q = f
m.v = f
m.u = n
m.y = n
m.s = c
i.v = f
i.z = f
i.x = j
i.w = n
i.q = d
i.o = m
assert f.p.x.v.y.t.txt == "j"