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

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.t: C = None
        self.z: E = None
        self.o: I = None
        self.w: E = None
        self.u: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.s: I = None
        self.t: D = None
        self.r: G = None
        self.q: C = None
        self.x: G = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: C = None
        self.u: E = None
        self.p: D = None
        self.z: C = None
        self.v: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: I = None
        self.v: A = None
        self.o: D = None
        self.w: A = None
        self.s: F = None
        self.p: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: C = None
        self.u: F = None
        self.s: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: G = None
        self.u: F = None
        self.t: B = None
        self.y: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.t: C = None
        self.z: E = None
        self.o: I = None
        self.w: E = None
        self.u: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.s: I = None
        self.t: D = None
        self.r: G = None
        self.q: C = None
        self.x: G = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: C = None
        self.u: E = None
        self.p: D = None
        self.z: C = None
        self.v: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: I = None
        self.v: A = None
        self.o: D = None
        self.w: A = None
        self.s: F = None
        self.p: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: C = None
        self.u: F = None
        self.s: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: G = None
        self.u: F = None
        self.t: B = None
        self.y: E = None
        self.txt = txt

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

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