In Python, you can characterize a capacity that takes variable number of contentions. You will figure out how to characterize such capacities utilizing default, watchword and self-assertive contentions in this article. 

List of chapters 


Variable Function Arguments 

Python Default Arguments 

Python Keyword Arguments 

Python Arbitrary Arguments 


In client characterized work point, we found out about characterizing a capacity and calling it. Something else, the capacity call will result into a blunder. Here is a precedent. 

def greet(name,msg): 

"""This capacity welcomes to 

the individual with the gave message""" 

print("Hello",name + ', ' + msg) 

greet("Monica","Good morning!") 


Hi Monica, hello! 

Here, the capacity welcome() has two parameters. 

Since, we have called this capacity with two contentions, it runs easily and we don't get any blunder. 

On the off chance that we call it with various number of contentions, the mediator will whine. The following is a call to this capacity with one and no contentions alongside their individual mistake messages. 

>>> greet("Monica") # just a single contention 

TypeError: welcome() missing 1 required positional contention: 'msg' 

>>> welcome() # no contentions 

TypeError: welcome() missing 2 required positional contentions: 'name' and 'msg' 

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Variable Function Arguments 

Up to this point capacities had settled number of contentions. In Python there are different approaches to characterize a capacity which can take variable number of contentions. 

Three distinct types of this compose are portrayed beneath. 

Python Default Arguments 

Capacity contentions can have default esteems in Python. 

We can give a default an incentive to a contention by utilizing the task administrator (=). Here is a precedent. 

def greet(name, msg = "Great morning!"): 


This capacity welcomes to 

the individual with the 

given message. 

In the event that message isn't given, 

it defaults to "Great 



print("Hello",name + ', ' + msg) 


greet("Bruce","How do you do?") 

In this capacity, the parameter name does not have a default esteem and is required (compulsory) amid a call. 

Then again, the parameter msg has a default estimation of "Hello!". In this way, it is discretionary amid a call. In the event that an esteem is given, it will overwrite the default esteem. 

Any number of contentions in a capacity can have a default esteem. Be that as it may, when we have a default contention, every one of the contentions to its privilege should likewise have default esteems. 

This way to state, non-default contentions can't pursue default contentions. For instance, on the off chance that we had characterized the capacity header above as: 

def greet(msg = "Hello!", name): 

We would get a mistake as: 

SyntaxError: non-default contention pursues default contention 

Python Keyword Arguments 

When we call a capacity with a few qualities, these qualities get allocated to the contentions as indicated by their position. 

For instance, in the above capacity welcome(), when we called it as greet("Bruce","How do you do?"), the esteem "Bruce" gets doled out to the contention name and also "How would you do?" to msg. 

Python enables capacities to be called utilizing watchword contentions. When we call works along these lines, the request (position) of the contentions can be changed. Following calls to the above capacity are altogether substantial and deliver a similar outcome. 

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>>> # 2 catchphrase contentions 

>>> greet(name = "Bruce",msg = "How would you do?") 

>>> # 2 watchword contentions (out of request) 

>>> greet(msg = "How would you do?",name = "Bruce") 

>>> # 1 positional, 1 watchword contention 

>>> greet("Bruce",msg = "How would you do?") 

As should be obvious, we can blend positional contentions with catchphrase contentions amid a capacity call. In any case, we should remember that catchphrase contentions must pursue positional contentions. 

Having a positional contention after watchword contentions will result into mistakes. For instance the capacity call as pursues: 

greet(name="Bruce","How do you do?") 

Will result into blunder as: 

SyntaxError: non-catchphrase arg after watchword arg 

Python Arbitrary Arguments 

Some of the time, we don't know ahead of time the quantity of contentions that will be passed into a function.Python enables us to deal with this sort of circumstance through capacity calls with self-assertive number of contentions. 

In the capacity definition we utilize a mark (*) before the parameter name to indicate this sort of contention. Here is a precedent. 

def greet(*names): 

"""This capacity welcomes all 

the individual in the names tuple.""" 

# names is a tuple with contentions 

for name in names: 




Hi Monica 

Hi Luke 

Hi Steve 

Hi John 

Here, we have called the capacity with numerous contentions. These contentions get wrapped up into a tuple before being passed into the capacity. Inside the capacity, we utilize a for circle to recover every one of the contentions back.

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