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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.w: B = None
        self.r: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.y: A = None
        self.s: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: D = None
        self.t: C = None
        self.s: C = None
        self.o: J = None
        self.p: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: E = None
        self.s: E = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.w: B = None
        self.r: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.y: A = None
        self.s: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: D = None
        self.t: C = None
        self.s: C = None
        self.o: J = None
        self.p: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: E = None
        self.s: E = None
        self.txt = txt

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

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

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

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