Web Standards Programmer's Reference: HTML, CSS, JavaScript®, Perl, Python®, and PHP

26.11. User-Defined Functions

You can create your own functions by using the def directive. User-defined functions have the following syntax:

def function_name(parameters):
    #  function statements

For example, to create a function to find the area of a circle you could use code similar to the following:

def areaofcircle()
    radius = input("Please enter the radius: ")
    area = 3.14+(radius**2)
    print "The area of the circle is", area

User-defined functions have the following attributes:

Attribute	Description
__doc__	documentation string
__name__	string version of function name
func_code	byte-compiled code object
func_defaults	default argument tuple
func_globals	global namespace dictionary

>>> areaofcircle.__doc__
>>> areaofcircle.__name__
'areaofcircle'
>>> areaofcircle.func_code
<code object areaofcircle at 0x403eab60, file
"<stdin>", line 1>
>>> areaofcircle.func_defaults
>>> areaofcircle.func_globals
{'lambdaFunc': <function <lambda> at 0x403ebbfc>, '__builtins__': <module
'__builtin__' (built-in)>, 'areaofcircle': <function areaofcircle at 0x403ebd4c>,
'datetime': <module 'datetime' from '/usr/lib/python2.4/lib-dynload/datetime.so'>,
'sys': <module 'sys' (built-in)>, 'time': <module 'time' from '/usr/lib/python2.4/
lib-dynload/time.so'>, '__name__': '__main__', 'os': <module 'os' from '/usr/lib/
python2.4/os.pyc'>, '__doc__': None}

26.11.1. Lamda Functions

Python allows for the creation of anonymous functions using the lamda keyword. Lamda expressions are similar to user-defined functions without ...