class A:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.q: A = None
        self.w: A = None
        self.u: F = None
        self.o: D = None
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: I = None
        self.o: G = None
        self.r: F = None
        self.z: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.q: C = None
        self.t: H = None
        self.y: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: B = None
        self.y: B = None
        self.r: I = None
        self.z: I = None
        self.s: I = None
        self.u: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: H = None
        self.z: H = None
        self.w: F = None
        self.p: H = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: I = None
        self.t: F = None
        self.z: A = None
        self.w: F = None
        self.p: F = None
        self.txt = txt

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

i = A("i")
d = B("d")
m = C("m")
e = D("e")
a = E("a")
l = F("l")
b = G("b")
c = H("c")
k = I("k")

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

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

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.q: A = None
        self.w: A = None
        self.u: F = None
        self.o: D = None
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: I = None
        self.o: G = None
        self.r: F = None
        self.z: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.q: C = None
        self.t: H = None
        self.y: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: B = None
        self.y: B = None
        self.r: I = None
        self.z: I = None
        self.s: I = None
        self.u: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: H = None
        self.z: H = None
        self.w: F = None
        self.p: H = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: I = None
        self.t: F = None
        self.z: A = None
        self.w: F = None
        self.p: F = None
        self.txt = txt

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

i = A("i")
d = B("d")
m = C("m")
e = D("e")
a = E("a")
l = F("l")
b = G("b")
c = H("c")
k = I("k")

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