class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.u: B = None
        self.r: D = None
        self.p: G = None
        self.t: H = None
        self.x: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: F = None
        self.y: D = None
        self.w: D = None
        self.q: I = None
        self.s: B = None
        self.r: G = None
        self.o: G = None
        self.x: E = None
        self.u: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.w: I = None
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: A = None
        self.w: F = None
        self.y: H = None
        self.u: D = None
        self.r: C = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: A = None
        self.p: G = None
        self.u: D = None
        self.o: A = None
        self.s: E = None
        self.q: G = None
        self.v: D = None
        self.x: C = None
        self.txt = txt

d = A("d")
e = B("e")
l = C("l")
i = D("i")
j = E("j")
f = F("f")
c = G("c")
h = H("h")
a = I("a")
m = J("m")

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

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

class C:
    def __init__(self, txt: str):
        self.p: F = None
        self.y: D = None
        self.w: D = None
        self.q: I = None
        self.s: B = None
        self.r: G = None
        self.o: G = None
        self.x: E = None
        self.u: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.w: I = None
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: A = None
        self.w: F = None
        self.y: H = None
        self.u: D = None
        self.r: C = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: A = None
        self.p: G = None
        self.u: D = None
        self.o: A = None
        self.s: E = None
        self.q: G = None
        self.v: D = None
        self.x: C = None
        self.txt = txt

d = A("d")
e = B("e")
l = C("l")
i = D("i")
j = E("j")
f = F("f")
c = G("c")
h = H("h")
a = I("a")
m = J("m")

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