-- your code goes here
local mystring='<span class="my-author"><a href="http://aaaa/author/abb-abbb/" title="Posts by abb" class="author" rel="author">abc xyz</a></span>'
local x, y = string.find(mystring,'<span class="my-author">', 0, true)
local w, z = string.find(mystring,'</a></span>', x, true)
local author
print(x,y,w,z)
if y==nil or w==nil then
print(author)
else
author = string.sub(mystring, y+1, w-1)
print(author)
end
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