How to Call a function in Python

In Python, a function is a block of code that performs a specific task and can be called from other parts of your program. Functions are an essential part of Python programming, and they allow you to write reusable, modular code that is easier to maintain and debug.

In this tutorial, we will learn how to call a function in Python. We will discuss the different ways you can pass arguments to a function, and we will also look at some common mistakes to avoid when calling functions in Python.

Calling function in Python

In Python, you can call a function by using its name followed by a pair of parentheses and optionally passing some arguments to the function inside the parentheses.

• Here’s an example of how to call a function in Python:
  # Define a function def greet(name): print("Hello, " + name) # Call the greet function and pass it a string argument greet("Rahul")

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  # Define a function def greet(name):   print("Hello, " + name)   # Call the greet function and pass it a string argument greet("Rahul")

  This code defines a function called `greet()` that takes a single argument, name, and prints a greeting using the value of the name argument. Then, the `greet()` function is called with the argument “Rahul”, which causes the function to print the following output:

  Hello, Rahul
  

• You can also pass multiple arguments to a function by separating them with commas. For example:
  # Define a function def greet(first_name, last_name): print("Hello, " + first_name + " " + last_name) # Call the greet function and pass it two string arguments greet("Rahul", "Kumar")

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  # Define a function def greet(first_name, last_name):   print("Hello, " + first_name + " " + last_name)   # Call the greet function and pass it two string arguments greet("Rahul", "Kumar")

  This code defines a function called `greet()` that takes two arguments: first_name and last_name. When the function is called with the arguments “Rahul” and “Kumar”, it prints the following output:

  Hello, Rahul Kumar
  

• It’s important to note that you must pass the correct number and type of arguments to a function when you call it. If you pass the wrong number or type of argument, you will get an error. For example:
  # Define a function def greet(name): print("Hello, " + name) # This will cause an error # because the greet function expects a single-string argument greet("Rahul", "Kumar")

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  # Define a function def greet(name):   print("Hello, " + name)   # This will cause an error # because the greet function expects a single-string argument greet("Rahul", "Kumar")

  You will get the error below:

  Traceback (most recent call last):
    File "b.py", line 6, in 
      greet("Rahul", "Kumar")
  TypeError: greet() takes 1 positional argument but 2 were given
  

Conclusion

In this tutorial, we learned how to call a function in Python. We learned how to pass arguments to a function, and we also looked at some common mistakes to avoid when calling functions in Python. We hope that this tutorial has helped you understand how to call functions in Python and that you are now ready to use functions in your own Python programs.