IsCancelation reports whether if given error is a cancelation error.

IsWarning checks if given error is either ErrObjectExists, ErrObjectIsNewer or ErrObjectSizesMatch.

ErrObjectExists indicates a specified object already exists.

ErrObjectIsNewer indicates a specified object is newer or same age.

ErrObjectIsNewerAndSizesMatch indicates the specified object is newer or same age and sizes of objects match.

ErrObjectSizesMatch indicates the sizes of objects match.

ErrObjectIsGlacier indicates the object is in Glacier storage class.

Error is the type that implements error interface.