create_autospec

Create a mock object using another object as a spec. Attributes on the
mock will use the corresponding attribute on the `spec` object as their
spec.

Functions or methods being mocked will have their arguments checked
to check that they are called with the correct signature.

If `spec_set` is True then attempting to set attributes that don't exist
on the spec object will raise an `AttributeError`.

If a class is used as a spec then the return value of the mock (the
instance of the class) will have the same spec. You can use a class as the
spec for an instance object by passing `instance=True`. The returned mock
will only be callable if instances of the mock are callable.

`create_autospec` will raise a `RuntimeError` if passed some common
misspellings of the arguments autospec and spec_set. Pass the argument
`unsafe` with the value True to disable that check.

`create_autospec` also takes arbitrary keyword arguments that are passed to
the constructor of the created mock.