var = [[Content-Disposition: attachment; filename="403.htm.en"
Content-Type: text/plain; name='403.htm.en'
Content-Transfer-Encoding: BASE64
]]
filename = string.match(var,"filename=\"(.+)\"")
print("filename = ", filename)
--https://pt.stackoverflow.com/q/77463/101
dmFyID0gW1tDb250ZW50LURpc3Bvc2l0aW9uOiBhdHRhY2htZW50OyBmaWxlbmFtZT0iNDAzLmh0bS5lbiIKICAgICBDb250ZW50LVR5cGU6IHRleHQvcGxhaW47IG5hbWU9JzQwMy5odG0uZW4nCiAgICAgQ29udGVudC1UcmFuc2Zlci1FbmNvZGluZzogQkFTRTY0CiAgICBdXQpmaWxlbmFtZSA9IHN0cmluZy5tYXRjaCh2YXIsImZpbGVuYW1lPVwiKC4rKVwiIikKcHJpbnQoImZpbGVuYW1lID0gIiwgZmlsZW5hbWUpCgotLWh0dHBzOi8vcHQuc3RhY2tvdmVyZmxvdy5jb20vcS83NzQ2My8xMDE=