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# Python2.x Python eval() Function [ Python Built-in Functions](#) * * * ## Description The **eval()** function is used to execute a string expression and return the value of the expression. **String expressions** can contain variables, function calls, operators, and other Python syntax elements. ### Syntax Here is the syntax for the eval() method: eval(expression[, globals[, locals]]) ### Parameters * expression -- The expression. * globals -- Variable scope, the global namespace. If provided, it must be a dictionary object. * locals -- Variable scope, the local namespace. If provided, it can be any mapping object. The eval() function parses the string `expression` as a Python expression and executes it within the specified namespace. ### Return Value The eval() function converts the string into the corresponding object and returns the result of the expression. * * * ## Examples The following examples demonstrate the use of the eval() method: ## Example 1 >>>x = 7>>>eval('3 * x')21>>>eval('pow(2,2)')4>>>eval('2 + 2')4>>>n=81>>>eval("n + 4")85 ## Example 2 # Execute a simple mathematical expression result =eval("2 + 3 * 4") print(result)# Output: 14 # Execute a variable reference x =10 result =eval("x + 5") print(result)# Output: 15 # Execute an expression in a specified namespace namespace ={'a': 2,'b': 3} result =eval("a + b", namespace) print(result)# Output: 5 > **Note:** The code executed by the eval() function has potential security risks. If an untrusted string is used as an expression, it could lead to code injection vulnerabilities. Therefore, the eval() function should be used with caution, and only trusted string expressions should be executed. [ Python Built-in Functions](#)