(resource)
return None
Get the ETag associated with a response returned from a call to 
    open_resource().

    If the resource was not returned from an HTTP server or the server did
    not specify an ETag for the resource, this will return None.
Get the ETag associated with a response returned from a call to 
    open_resource().
Get the ETag associated with a response returned from a call to open_resource () .
def get_etag(resource):
    """
    Get the ETag associated with a response returned from a call to 
    open_resource().

    If the resource was not returned from an HTTP server or the server did
    not specify an ETag for the resource, this will return None.
    """

    if hasattr(resource, "info"):
        return resource.info().getheader("ETag")
    return None
def get_etag ( resource ) : if hasattr ( resource , "info" ) : return resource . info ( ) . getheader ( "ETag" ) return None