


Accessing Variable Values from String Names
Python provides various techniques to retrieve the value of a variable when its name is stored in a string. Understanding these methods can be valuable in dynamic programming scenarios.
Getting Global Variable Value
To access a global variable's value, you can utilize the globals() function. It returns a dictionary containing all currently defined global variables. For instance:
def foo(a): # Retrieve the variable name from the string variable_name = a # Check if the variable is global if variable_name in globals(): return globals()[variable_name]
Note on Namespace
The above technique assumes that the variable is defined in the global namespace. If it's defined in a different namespace, you'll need access to that namespace to retrieve its value.
Caution with eval
While eval() can also be used to dynamically access variables, it's recommended to exercise caution. Using eval() with untrusted input can pose security risks.
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