def prepare(doc):
doc.mustache_files = doc.get_metadata('<STR_LIT>')<EOL>if isinstance(doc.mustache_files, basestring):  <EOL><INDENT>if not doc.mustache_files:<EOL><INDENT>doc.mustache_files = None  <EOL><DEDENT>else:<EOL><INDENT>doc.mustache_files = [ doc.mustache_files ]  <EOL><DEDENT><DEDENT>if doc.mustache_files is not None:<EOL><INDENT>doc.mustache_hashes = [yaml.load(open(file, '<STR_LIT:r>').read()) for file in doc.mustache_files]<EOL>doc.mhash = { k: v for mdict in doc.mustache_hashes for k, v in mdict.items() }  <EOL>doc.mrenderer = pystache.Renderer(escape=lambda u: u, missing_tags='<STR_LIT:strict>')<EOL><DEDENT>else:<EOL><INDENT>doc.mhash = None<EOL><DEDENT>
Parse metadata to obtain list of mustache templates,
        then load those templates.