Python Global variables
A global variable is a variable which is accessible in multiple scopes. In Python, it is better to use a single module to hold all the global variables you want to use and whenever you want to use them, just import this module, and then you can modify that and it will be visible in other modules that do the same.
Create a Global module
Create a Python program file to access global variable
Create another Python program to test value is changed or not
Using global variables in a function
A global can be accessed by any function , but it can only be modified if you explicitly declare it with the 'global' keyword inside the function. To use global variables inside a function, you need to do global < varName > inside the function. Keep in mind, that you only need to declare them global inside the function if you want to do assignments / change them. global is not needed for printing and accessing.
Global and Local Variables in Python
Local variables can only be reached in their scope. For ex. check with the following two local variables.
The error showing because the variable x has only local scope.
Moreover, If a variable with same name is defined inside the scope of function as well then it will print the value given inside the function only and not the global value.
Python Data Types and Variables
Every variable in Python is considered as an object . Variables in Python follow the standard nomenclature of an alphanumeric name beginning in a letter or underscore. Based on the data type of a variable, the interpreter allocates memory and decides what can be stored in the reserved memory . You do not need to declare variables before using them, or declare their type. Variable names are case sensitive . Most variables in Python are local in scope to their own function or class.
More on.... Python Data Types and Variables
Looking for a Python job ?
Chances are you will need to prove that you know how to work with Python. These Python Interview Questions have been designed especially to get you acquainted with the nature of questions you may encounter during your interview for the subject of Python Programming . Here are the top objective type sample Python Interview questions and their answers are given just below to them. These sample questions are framed by our experts team who trains for Python training to give you an idea of type of questions which may be asked in interview.
Go to... Python Interview Questions
- Python Interview Questions FAQ - 1
- Python Interview Questions FAQ - 2
- What is python used for?
- Is Python interpreted, or compiled, or both?
- Explain how python is interpreted
- How do I install pip on Windows?
- How do you protect Python source code?
- What are the disadvantages of the Python?
- How would you achieve web scraping in Python?
- How to Python Script executable on Unix
- What is the difference between .py and .pyc files?
- What is __init__.py used for in Python?
- What does __name__=='__main__' in Python mean?
- What is docstring in Python?
- What is the difference between runtime and compile time?
- How to use *args and **kwargs in Python
- Purpose of "/" and "//" operator in python?
- What is the purpose pass statement in python?
- Why isn't there a switch or case statement in Python?
- How does the ternary operator work in Python?
- What is the purpose of "self" in Python
- How do you debug a program in Python?
- What are literals in python?
- What is Python's parameter passing mechanism?
- What is the process of compilation and Loading in python?
- Is there a tool to help find bugs or perform static analysis?
- What does the 'yield' keyword do in Python?
- Comparison Operators != is not equal to in Python
- What is the difference between 'is' and '==' in python
- What is the difference between = and == in Python?
- How are the functions help() and dir() different?
- What is the python keyword "with" used for?
- Is all the memory freed when Python exits?
- Difference between Mutable and Immutable in Python
- Explain split() methods of "re" module in Python
- Accessor and Mutator methods in Python
- How to Implement an 'enum' in Python
- Important characteristics of Python Objects
- How to determine the type of instance and inheritance in Python
- How would you implement inheritance in Python?
- How is Inheritance and Overriding methods are related?
- How can you create a copy of an object in Python?
- How to avoid having class data shared among instances in Python?
- Static class variables in Python
- Difference between @staticmethod and @classmethod in Python
- How to Get a List of Class Attributes in Python
- Does Python supports interfaces like in Java or C#?
- What is used to create Unicode string in Python?
- Difference between lists and tuples in Python?
- What are differences between List and Dictionary in Python
- Different file processing modes supported by Python
- How do you append to a file in Python?
- What are the differences between the threading and multiprocessing?
- Is there any way to kill a Thread in Python?
- What is the use of lambda in Python?
- What is map, filter and reduce in python?
- Is monkey patching considered good programming practice?
- What is "typeerror: 'module' object is not callable"
- Python: TypeError: unhashable type: 'list'