Python None
None is a special constant in Python that represents the absence of a value.
Its data type is NoneType, and None is the only instance of a NoneType object.
NoneType
Variables can be assigned None to indicate "no value" or "not set".
Example
x = None
print(x)
Use type() to see the type of a None value.
Example
x = None
print(type(x))
Comparing to None
To compare a value to None, use the identity operator is or is not
Example
result = None
if result is None:
print("No result yet")
else:
print("Result is ready")
Example
result = None
if result is not None:
print("Result is ready")
else:
print("No result yet")
True or False
None evaluates to False in a boolean context.
Example
print(bool(None))
Functions returning None
Functions that do not explicitly return a value return None by default.
Example
def myfunc():
x = 5
x = myfunc()
print(x)
