Identifiers:
In Python, an identifier is a name used to identify a variable, function, class, module, or other objects. It is a user-defined name that follows certain rules and conventions.
Key characteristics and rules for identifiers in Python:
Valid Characters: An identifier can contain letters (both uppercase and lowercase), digits, and underscores (_). However, it cannot start with a digit.
Case-Sensitivity: Python is case-sensitive, so myVar and myvar are considered different identifiers.
Naming Convention: Python follows the PEP 8 style guide, which suggests using lowercase letters and underscores to separate words in variable and function names (e.g., my_variable, function_name). For class names, the convention is to use CamelCase (e.g., MyClass, MyClassMethod).
Reserved Words: Identifiers cannot be a Python keyword or reserved word. They are words that have predefined meanings and cannot be used as identifiers. For example, you cannot use if, else, for, or import as identifiers.
Meaningful Names: It is recommended to choose meaningful and descriptive names for identifiers to enhance code readability and maintainability.
Examples of invalid identifiers in Python:
2myvariable # Starts with a digit (not allowed)
if # Reserved word (not allowed)
my-variable # Contains a hyphen (not allowed)
Examples of valid identifiers in Python:
my_variable = 'Age'
count = 4
total_sum = 24
PI = 'a'
MyClass = 'High'
calculate_area = 235
