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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: A = None
        self.x: F = None
        self.q: I = None
        self.v: H = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.o: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: C = None
        self.y: E = None
        self.p: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: F = None
        self.q: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: A = None
        self.x: F = None
        self.q: I = None
        self.v: H = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.o: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: C = None
        self.y: E = None
        self.p: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: F = None
        self.q: G = None
        self.txt = txt

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

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