A variable is only available from inside the region it is created. This is called scope.
Local Scope
A variable created inside a function belongs to the local scope of that function, and can only be used inside that function.
Example
A variable created inside a function is available inside that function:
def myfunc():
x = 300
print(x)
myfunc()
Function Inside Function
As explained in the example above, the variable x is not available outside the function, but it is available for any function inside the function: Continue reading Python Scope