def call(template)
builder = StringIO.new
builder << "require 'axlsx';"
builder << "xlsx_author = defined?(xlsx_author).nil? ? nil : xlsx_author;"
builder << "xlsx_created_at = defined?(xlsx_created_at).nil? ? nil : xlsx_created_at;"
builder << "xlsx_use_shared_strings = defined?(xlsx_use_shared_strings).nil? ? nil : xlsx_use_shared_strings;"
builder << "xlsx_package = Axlsx::Package.new("
builder << ":author => xlsx_author,"
builder << ":created_at => xlsx_created_at,"
builder << ":use_shared_strings => xlsx_use_shared_strings);"
builder << template.source
builder << ";xlsx_package.to_stream.string;"
builder.string
end