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

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

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

class D:
    def __init__(self, txt: str):
        self.u: F = None
        self.o: G = None
        self.z: G = None
        self.x: E = None
        self.s: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: E = None
        self.v: D = None
        self.q: D = None
        self.y: B = None
        self.p: E = None
        self.r: J = None
        self.z: B = None
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: C = None
        self.q: I = None
        self.u: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.w: A = None
        self.q: C = None
        self.o: B = None
        self.u: J = None
        self.y: G = None
        self.v: A = None
        self.x: B = None
        self.p: B = None
        self.z: J = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.u: F = None
        self.o: G = None
        self.z: G = None
        self.x: E = None
        self.s: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: E = None
        self.v: D = None
        self.q: D = None
        self.y: B = None
        self.p: E = None
        self.r: J = None
        self.z: B = None
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: C = None
        self.q: I = None
        self.u: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.w: A = None
        self.q: C = None
        self.o: B = None
        self.u: J = None
        self.y: G = None
        self.v: A = None
        self.x: B = None
        self.p: B = None
        self.z: J = None
        self.txt = txt

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

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

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