You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mz.rb
    path of file: ./repos/grinder/node/lib/metasm/metasm/exe_format
    
    the code of the file until where you have to start completion: #    This file is part of Metasm, the Ruby assembly manipula
    
	def encode_fix_checksum
		@encoded.ptr = 0
		decode_header
		mzlen = @header.cp * 512 + @header.cblp
		@encoded.ptr = 0
		csum = -@header.csum
		(mzlen/2).times { csum += decode_word }
		csum &= 0xffff
		@header.csum = csum
		hdr = @header.encode(self, nil)
		@encoded[0, hdr.length] = hdr
	end