lock() unlock() Three locking mechanisms are used—dot locking and, if available, the flock() and lockf() system calls. For MH mailboxes, locking the mailbox means locking the .mh_sequences file and, only for the duration of any operations that affect them, locking individual message files.

class tkinter.tix.Form The Form geometry manager based on attachment rules for all Tk widgets.

divide(x, y) Return x divided by y.

urllib.parse.unquote_plus(string, encoding='utf-8', errors='replace') Like unquote(), but also replace plus signs by spaces, as required for unquoting HTML form values. string must be a str. Example: unquote_plus('/El+Ni%C3%B1o/') yields '/El Niño/'.

os.pwrite(fd, str, offset) Write bytestring to a file descriptor, fd, from offset, leaving the file offset unchanged. Availability: Unix. New in version 3.3.

importlib.machinery.all_suffixes() Returns a combined list of strings representing all file suffixes for modules recognized by the standard import machinery. This is a helper for code which simply needs to know if a filesystem path potentially refers to a module without needing any details on the kind of module (for example, inspect.getmodulename()). New in version 3.3.

remove(key) __delitem__(key) discard(key) Delete the message corresponding to key from the mailbox. If no such message exists, a KeyError exception is raised if the method was called as remove() or __delitem__() but no exception is raised if the method was called as discard(). The behavior of discard() may be preferred if the underlying mailbox format supports concurrent modification by other processes.

xml.dom.pulldom.parse(stream_or_string, parser=None, bufsize=None) Return a DOMEventStream from the given input. stream_or_string may be either a file name, or a file-like object. parser, if given, must be an XMLReader object. This function will change the document handler of the parser and activate namespace support; other parser configuration (like setting an entity resolver) must have been done in advance.

operator.attrgetter(attr) operator.attrgetter(*attrs) Return a callable object that fetches attr from its operand. If more than one attribute is requested, returns a tuple of attributes. The attribute names can also contain dots. For example: After f = attrgetter('name'), the call f(b) returns b.name. After f = attrgetter('name', 'date'), the call f(b) returns (b.name, b.date). After f = attrgetter('name.first', 'name.last'), the call f(b) returns (b.name.first, b.name.last). Equivalent to:

HTMLParser.handle_starttag(tag, attrs) This method is called to handle the start of a tag (e.g. <div id="main">). The tag argument is the name of the tag converted to lower case. The attrs argument is a list of (name, value) pairs containing the attributes found inside the tag’s <> brackets. The name will be translated to lower case, and quotes in the value have been removed, and character and entity references have been replaced. For instance, for the tag <A HREF="https://www