annotation valuesspecified as name:value (or name:value=default when defaults are presentthis is simply additional syntax for arguments and does not augment or change the argument-ordering rules described here the function itself can also have an annotation valuegiven as def ()->value python attaches annotation values to the function object see the discussion of function annotation in for more details keyword and default examples this is all simpler in code than the preceding descriptions may imply if you don' use any special matching syntaxpython matches names by position from left to rightlike most other languages for instanceif you define function that requires three argumentsyou must call it with three argumentsdef (abc)print(abcf( herewe pass by position-- is matched to is matched to and so on (this works the same in python and xbut extra tuple parentheses are displayed in because we're using print calls againkeywords in pythonthoughyou can be more specific about what goes where when you call function keyword arguments allow us to match by nameinstead of by position using the same functionf( = = = the = in this callfor examplemeans send to the argument named more formallypython matches the name in the call to the argument named in the function definition' headerand then passes the value to that argument the net effect of this call is the same as that of the prior callbut notice that the left-to-right order of the arguments no longer matters when keywords are used because arguments are matched by namenot by position it' even possible to combine positional and keyword arguments in single call in this caseall positionals are matched first from left to right in the headerbefore keywords are matched by namef( = = gets by positionb and passed by name when most people see this the first timethey wonder why one would use such tool keywords typically have two roles in python firstthey make your calls bit more selfdocumenting (assuming that you use better argument names than aband !for examplea call of this form arguments