Comparison methods for sppasTag.
Label'tags can be of 3 types in anndata (str, num, bool) so that this class allows to create different comparison methods depending on the type of the tags.
Example
> Three different ways to compare a tag content to a given string
Example
>>> tc = sppasTagCompare()
>>> tc.exact(sppasTag("abc"), u("abc"))
>>> tc.methods['exact'](sppasTag("abc"), u("abc"))
>>> tc.get('exact')(sppasTag("abc"), u("abc"))