def __setitem__(self, key, value):
if self.environ.get('<STR_LIT>'):<EOL><INDENT>raise KeyError('<STR_LIT>')<EOL><DEDENT>self.environ[key] = value<EOL>todelete = ()<EOL>if key == '<STR_LIT>':<EOL><INDENT>todelete = ('<STR_LIT:body>', '<STR_LIT>', '<STR_LIT>', '<STR_LIT>', '<STR_LIT>', '<STR_LIT>')<EOL><DEDENT>elif key == '<STR_LIT>':<EOL><INDENT>todelete = ('<STR_LIT>', '<STR_LIT>')<EOL><DEDENT>elif key.startswith('<STR_LIT>'):<EOL><INDENT>todelete = ('<STR_LIT>', '<STR_LIT>')<EOL><DEDENT>for key in todelete:<EOL><INDENT>self.environ.pop('<STR_LIT>' + key, None)<EOL><DEDENT>
Change an environ value and clear all caches that depend on it.