heapq.nlargest(n, iterable, key=None) Return a list with the n largest elements from the dataset defined by iterable. key, if provided, specifies a function of one argument that is used to extract a comparison key from each element in the iterable: key=str.lower Equivalent to: sorted(iterable, key=key, reverse=True)[:n]

heapq.nsmallest(n, iterable, key=None) Return a list with the n smallest elements from the dataset defined by iterable. key, if provided, specifies a function of one argument that is used to extract a comparison key from each element in the iterable: key=str.lower Equivalent to: sorted(iterable, key=key)[:n]

heapq.merge(*iterables, key=None, reverse=False) Merge multiple sorted inputs into a single sorted output (for example, merge timestamped entries from multiple log files). Returns an iterator over the sorted values. Similar to sorted(itertools.chain(*iterables)) but returns an iterable, does not pull the data into memory all at once, and assumes that each of the input streams is already sorted (smallest to largest). Has two optional arguments which must be specified as keyword arguments. key

help([object]) Invoke the built-in help system. (This function is intended for interactive use.) If no argument is given, the interactive help system starts on the interpreter console. If the argument is a string, then the string is looked up as the name of a module, function, class, method, keyword, or documentation topic, and a help page is printed on the console. If the argument is any other kind of object, a help page on the object is generated. This function is added to the built-in nam

hex(x) Convert an integer number to a lowercase hexadecimal string prefixed with “0x”, for example: >>> hex(255) '0xff' >>> hex(-42) '-0x2a' If x is not a Python int object, it has to define an __index__() method that returns an integer. See also int() for converting a hexadecimal string to an integer using a base of 16. Note To obtain a hexadecimal string representation for a float, use the float.hex() method.

heapq.heapify(x) Transform list x into a heap, in-place, in linear time.

hashlib.pbkdf2_hmac(hash_name, password, salt, iterations, dklen=None) The function provides PKCS#5 password-based key derivation function 2. It uses HMAC as pseudorandom function. The string hash_name is the desired name of the hash digest algorithm for HMAC, e.g. ‘sha1’ or ‘sha256’. password and salt are interpreted as buffers of bytes. Applications and libraries should limit password to a sensible length (e.g. 1024). salt should be about 16 or more bytes from a proper source, e.g. os.uran

heapq.heapreplace(heap, item) Pop and return the smallest item from the heap, and also push the new item. The heap size doesn’t change. If the heap is empty, IndexError is raised. This one step operation is more efficient than a heappop() followed by heappush() and can be more appropriate when using a fixed-size heap. The pop/push combination always returns an element from the heap and replaces it with item. The value returned may be larger than the item added. If that isn’t desired, conside

heapq.heappushpop(heap, item) Push item on the heap, then pop and return the smallest item from the heap. The combined action runs more efficiently than heappush() followed by a separate call to heappop().

heapq.heappush(heap, item) Push the value item onto the heap, maintaining the heap invariant.