'Updates stemming options used by indexing for the search domain.
:type domain_name: string
:param domain_name: A string that represents the name of a
domain. Domain names must be unique across the domains
owned by an account within an AWS region. Domain names
must start with a letter or number and can contain the
following characters: a-z (lowercase), 0-9, and -
(hyphen). Uppercase letters and underscores are not
allowed.
:type stems: string
:param stems: Maps terms to their stems.  The JSON object
has a single key called "stems" whose value is a
dict mapping terms to their stems. The maximum size
of a stemming document is 500KB.
Example: {"stems":{"people": "person", "walking":"walk"}}
:raises: BaseException, InternalException, InvalidTypeException,
LimitExceededException, ResourceNotFoundException'

def update_stemming_options(self, domain_name, stems):

    doc_path = ('update_stemming_options_response', 'update_stemming_options_result', 'stems')
    params = {'DomainName': domain_name, 'Stems': stems}
    return self.get_response(doc_path, 'UpdateStemmingOptions', params, verb='POST')
