def create(self, username, password):
data = values.of({'<STR_LIT>': username, '<STR_LIT>': password, })<EOL>payload = self._version.create(<EOL>'<STR_LIT:POST>',<EOL>self._uri,<EOL>data=data,<EOL>)<EOL>return CredentialInstance(<EOL>self._version,<EOL>payload,<EOL>account_sid=self._solution['<STR_LIT>'],<EOL>credential_list_sid=self._solution['<STR_LIT>'],<EOL>)<EOL>
Create a new CredentialInstance

:param unicode username: The username for this credential.
:param unicode password: The password will not be returned in the response.

:returns: Newly created CredentialInstance
:rtype: twilio.rest.api.v2010.account.sip.credential_list.credential.CredentialInstance