>>> import struct
>>> print(struct.__doc__)
Functions to convert between Python values and C structs.
Python bytes objects are used to hold the data representing the C struct
and also as format strings (explained below) to describe the layout of data
in the C struct.
The optional first format char indicates byte order, size and alignment:
 @: native order, size & alignment (default)
 =: native order, std. size & alignment
 <: little-endian, std. size & alignment
 >: big-endian, std. size & alignment
 !: same as >
The remaining chars indicate types of args and must match exactly;
these can be preceded by a decimal repeat count:
 x: pad byte (no data); c:char; b:signed byte; B:unsigned byte;
 ?: _Bool (requires C99; if not available, char is used instead)
 h:short; H:unsigned short; i:int; I:unsigned int;
 l:long; L:unsigned long; f:float; d:double; e:half-float.
Special cases (preceding decimal count indicates length):
 s:string (array of char); p: pascal string (with count byte).
Special cases (only available in native format):
 n:ssize_t; N:size_t;
 P:an integer type that is wide enough to hold a pointer.
Special case (not in native mode unless 'long long' in platform C):
 q:long long; Q:unsigned long long
Whitespace between formats is ignored.
The variable struct.error is an exception raised on errors.