class A:
    def __init__(self, txt: str):
        self.p: F = None
        self.s: E = None
        self.q: D = None
        self.x: I = None
        self.r: J = None
        self.o: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.x: E = None
        self.y: I = None
        self.q: D = None
        self.t: E = None
        self.u: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.w: C = None
        self.o: H = None
        self.s: H = None
        self.r: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: H = None
        self.x: D = None
        self.s: J = None
        self.w: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.z: F = None
        self.v: F = None
        self.q: J = None
        self.u: D = None
        self.x: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.x: E = None
        self.y: I = None
        self.q: D = None
        self.t: E = None
        self.u: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.w: C = None
        self.o: H = None
        self.s: H = None
        self.r: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: H = None
        self.x: D = None
        self.s: J = None
        self.w: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.z: F = None
        self.v: F = None
        self.q: J = None
        self.u: D = None
        self.x: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

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

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