class A:
    def __init__(self, txt: str):
        self.x: G = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.r: D = None
        self.v: G = None
        self.q: A = None
        self.p: D = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.r: D = None
        self.v: G = None
        self.q: A = None
        self.p: D = None
        self.txt = txt

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

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

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

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

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