parse(format_string) Loop over the format_string and return an iterable of tuples (literal_text, field_name, format_spec, conversion). This is used by vformat() to break the string into either literal text, or replacement fields. The values in the tuple conceptually represent a span of literal text followed by a single replacement field. If there is no literal text (which can happen if two replacement fields occur consecutively), then literal_text will be a zero-length string. If there is no

get_value(key, args, kwargs) Retrieve a given field value. The key argument will be either an integer or a string. If it is an integer, it represents the index of the positional argument in args; if it is a string, then it represents a named argument in kwargs. The args parameter is set to the list of positional arguments to vformat(), and the kwargs parameter is set to the dictionary of keyword arguments. For compound field names, these functions are only called for the first component of t

get_field(field_name, args, kwargs) Given field_name as returned by parse() (see above), convert it to an object to be formatted. Returns a tuple (obj, used_key). The default version takes strings of the form defined in PEP 3101, such as “0[name]” or “label.title”. args and kwargs are as passed in to vformat(). The return value used_key has the same meaning as the key parameter to get_value().

format_field(value, format_spec) format_field() simply calls the global format() built-in. The method is provided so that subclasses can override it.

format(format_string, *args, **kwargs) The primary API method. It takes a format string and an arbitrary set of positional and keyword arguments. It is just a wrapper that calls vformat(). Deprecated since version 3.5: Passing a format string as keyword argument format_string has been deprecated.

convert_field(value, conversion) Converts the value (returned by get_field()) given a conversion type (as in the tuple returned by the parse() method). The default version understands ‘s’ (str), ‘r’ (repr) and ‘a’ (ascii) conversion types.

check_unused_args(used_args, args, kwargs) Implement checking for unused arguments if desired. The arguments to this function is the set of all argument keys that were actually referred to in the format string (integers for positional arguments, and strings for named arguments), and a reference to the args and kwargs that was passed to vformat. The set of unused args can be calculated from these parameters. check_unused_args() is assumed to raise an exception if the check fails.

class string.Formatter The Formatter class has the following public methods: format(format_string, *args, **kwargs) The primary API method. It takes a format string and an arbitrary set of positional and keyword arguments. It is just a wrapper that calls vformat(). Deprecated since version 3.5: Passing a format string as keyword argument format_string has been deprecated. vformat(format_string, args, kwargs) This function does the actual work of formatting. It is exposed as a sepa

string.digits The string '0123456789'.

string.capwords(s, sep=None) Split the argument into words using str.split(), capitalize each word using str.capitalize(), and join the capitalized words using str.join(). If the optional second argument sep is absent or None, runs of whitespace characters are replaced by a single space and leading and trailing whitespace are removed, otherwise sep is used to split and join the words.