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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def replace_media(self,src_file,dst_file):
 """Replace one media by another one into a docx This has been done mainly because it is not possible to add images in docx header/footer. With this function, put a dummy picture in your header/footer, then specify it with its replacement in this function Syntax: tpl.replace_media('dummy_media_to_replace.png','media_to_paste.jpg') Note: for images, the aspect ratio will be the same as the replaced image Note2 : it is important to have the source media file as it is required to calculate its CRC to find them in the docx """

        with open(dst_file, 'rb') as fh:
            crc = self.get_file_crc(src_file)
            self.crc_to_new_media[crc] = fh.read()