Dynamic module-level lookup
A module needs to look up a setting by a name held in a string.
Python · Function
globals
globals() returns the dictionary representing the current module namespace. In a function, that namespace belongs to the module where the function was defined.
How it works
Calling globals() returns the dictionary that implements the current module namespace. Inside a function, that namespace is determined when the function is defined, so the same module dictionary is returned even if the function is called from elsewhere.
Syntax
globals()Returns
The dictionary implementing the current module namespace.
Key points
- globals() returns the dictionary used for the current module's namespace.
- A function uses the global namespace associated with its defining module.
- Calling the function from another location does not switch its global namespace.
- At module level, globals() and locals() refer to the same dictionary.
Example: Read a module global
APP_NAME = "worker"
def configured_name():
return globals()["APP_NAME"]
print(configured_name())The function reads a module-level setting through the dictionary returned by globals().
When to use it
Supplying an execution namespace
Code needs to provide its module namespace to dynamic execution.
Module introspection
A debugging utility needs to inspect names defined by its module.
Interview questions
QWhat does globals() return?
globals() returns the dictionary implementing the current module namespace. It takes no arguments and can be used to inspect or access module-level names.
Follow-up: How does it behave inside a function? It still returns the namespace of the module where that function was defined.
QWhat namespace does globals() represent?
At module scope, globals() provides the module namespace dictionary, including names defined at that scope. The returned object is a dictionary rather than a separate snapshot.
Follow-up: What distinction matters in a function? The relevant module is fixed when the function is defined.
QWhat are the signature and return value of globals()?
The function has no parameters and returns the dictionary implementing the current module namespace. A caller can use the result for dynamic name lookup, although ordinary named access is usually clearer.
Follow-up: How could dynamic execution use it? The documentation notes that globals() can be useful as the global namespace passed to exec().
Related
locals()exec()eval()