What are the different ways the asterisk (*) character is used in Python functions?

What is the Significance of the Asterisk (*) Character in Python?

In Python, the asterisk (*) symbol holds a unique significance in function definitions and calls.

Function Definitions:

In function definitions, followed by an identifier (e.g., identifier) indicates that the function can take an arbitrary number of positional arguments. These arguments will be collected into a tuple called identifier.

Function Calls:

• can also be used in function calls to specify that the function should unpack its positional or keyword arguments from a sequence or dictionary.

Positional Arguments:

*args captures any excess positional arguments passed to the function. These arguments are stored as a tuple in the identifier specified after the asterisk.

Example:

def sum_args(*nums):
    total = 0
    for num in nums:
        total += num
    return total

The following function calls would work with the above definition:

sum_args(1, 2, 3)  # Returns 6
sum_args(1, 2, 3, 4, 5)  # Returns 15

Keyword Arguments:

**kwargs captures any excess keyword arguments passed to the function. These arguments are stored as a dictionary in the identifier specified after the asterisk.

Example:

def print_info(**person):
    for key, value in person.items():
        print(f"{key}: {value}")

The following function calls would work with the above definition:

print_info(name="John", age=30)  # Prints "name: John", "age: 30"
print_info(name="Mary", age=25, city="Boston")  # Prints "name: Mary", "age: 25", "city: Boston"

Unpacking Sequences and Dictionaries:

• can also be used in function calls to unpack a tuple or dictionary into function arguments.

Example (Unpack Tuple):

def sum_nums(a, b, c):
    return a + b + c

args = (1, 2, 3)
sum_nums(*args)  # Returns 6

Example (Unpack Dictionary):

def print_details(**details):
    print("Name:", details["name"])
    print("Age:", details["age"])

kwargs = {"name": "Bob", "age": 35}
print_details(**kwargs)  # Prints "Name: Bob", "Age: 35"

By understanding the significance of the asterisk (*) in Python, you can effectively work with positional and keyword arguments in function definitions and calls.

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