class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.z: J = None
        self.w: E = None
        self.p: J = None
        self.s: J = None
        self.v: H = None
        self.o: J = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: J = None
        self.s: A = None
        self.z: C = None
        self.w: J = None
        self.t: H = None
        self.v: F = None
        self.o: J = None
        self.y: F = None
        self.p: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: C = None
        self.v: E = None
        self.t: D = None
        self.r: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: A = None
        self.v: C = None
        self.w: E = None
        self.x: F = None
        self.t: I = None
        self.o: G = None
        self.s: B = None
        self.txt = txt

m = A("m")
i = B("i")
l = C("l")
n = D("n")
j = E("j")
e = F("e")
h = G("h")
c = H("c")
b = I("b")
g = J("g")

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: J = None
        self.s: A = None
        self.z: C = None
        self.w: J = None
        self.t: H = None
        self.v: F = None
        self.o: J = None
        self.y: F = None
        self.p: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: C = None
        self.v: E = None
        self.t: D = None
        self.r: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: A = None
        self.v: C = None
        self.w: E = None
        self.x: F = None
        self.t: I = None
        self.o: G = None
        self.s: B = None
        self.txt = txt

m = A("m")
i = B("i")
l = C("l")
n = D("n")
j = E("j")
e = F("e")
h = G("h")
c = H("c")
b = I("b")
g = J("g")

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