'**SUMMARY**
Return only the features inside the region. where region can be a bounding box,
bounding circle, a list of tuples in a closed polygon, or any other featutres.
**PARAMETERS**
* *region*
* A bounding box - of the form (x,y,w,h) where x,y is the upper left corner
* A bounding circle of the form (x,y,r)
* A list of x,y tuples defining a closed polygon e.g. ((x,y),(x,y),....)
* Any two dimensional feature (e.g. blobs, circle ...)
**RETURNS**
Returns a featureset of features that are inside the region.
**EXAMPLE**
>>> img = Image("Lenna")
>>> blobs = img.findBlobs()
>>> b = blobs[-1]
>>> lines = img.findLines()
>>> inside = lines.inside(b)
**NOTE**
This currently performs a bounding box test, not a full polygon test for speed.'

def inside(self, region):

    fs = FeatureSet()
    for f in self:
        if f.isContainedWithin(region):
            fs.append(f)
    return fs
