code: def credentials(self, credentials):
          
          if credentials is not None and len(credentials) > 1024:
              raise ValueError("Invalid value for `credentials`, length must be less than or equal to `1024`")
          if credentials is not None and len(credentials) < 1:
              raise ValueError("Invalid value for `credentials`, length must be greater than or equal to `1`")
          if credentials is not None and not re.search('[\\x21-\\x7E \\t]*', credentials):
              raise ValueError("Invalid value for `credentials`, must be a follow pattern or equal to `/[\\x21-\\x7E \\t]*/`")
  
          self._credentials = credentials
docs: Sets the credentials of this WebAuthorization.
          The confidential portion of the `Authorization` header that follows the `type` field.  This field is write-only. It is omitted by read operations.  If authorization is required, the `credentials` value must be provided whenever a File Source is created or modified. An update to a dataset that does not change the File Source may omit the `credentials` field--the update will preserve the previous value.
  
          :param credentials: The credentials of this WebAuthorization.
          :type: str