Variables, Classes and functions should be defined before they are used, otherwise the code will fail.
Noncompliant code example
def noncompliant():
foo() # Noncompliant
foo = sum
func() # Noncompliant
def func():
pass
MyClass() # Noncompliant
class MyClass:
pass
Compliant solution
def compliant():
foo = sum
foo()
def func():
pass
func()
class MyClass:
pass
MyClass()
