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Python isidentifier()

The isidentifier() function in python helps to check whether the specified string is a valid identifier or not. The function returns true if it is a valid identifier otherwise it returns false.


string.isidentifier() 
 

isidentifier() Parameters:

The isidentifier() method doesn't take any parameters. A string is said to be a valid identifier if it contains alphanumeric letters (a-z) and numbers(0-9), or underscores (_), and can be of any length. Also, the valid identifier cannot start with a number, or contain any spaces.

isidentifier() Return Value

The return value is always a boolean value.In the case of an empty string, the function will return False.

Input Return Value
if a valid identifier True
if not a valid identifier False

Examples of isidentifier() method in Python

Example 1: How isidentifier() works in Python?


string = 'Programming'
print(string.isidentifier())

string = 'Pro gramming'
print(string.isidentifier())

string = '12Programming'
print(string.isidentifier())

string = ''
print(string.isidentifier())
 

Output:


True
False
False
False

Example 2: Example of isidentifier() method


string1 = "Python"
string2 = "Python002"
string3 = "1python"
string4 = "hi python"

print(string1.isidentifier())
print(string2.isidentifier())
print(string3.isidentifier())
print(string4.isidentifier())
 

Output:


True
True
False
False