code: def normalizeBPointType(value):
      
      allowedTypes = ['corner', 'curve']
      if not isinstance(value, basestring):
          raise TypeError("bPoint type must be a string, not %s."
                          % type(value).__name__)
      if value not in allowedTypes:
          raise ValueError("bPoint type must be 'corner' or 'curve', not %r."
                           % value)
      return unicode(value)
docs: Normalizes bPoint type.
  
      * **value** must be an string.
      * **value** must be one of the following:
  
        +--------+
        | corner |
        +--------+
        | curve  |
        +--------+
  
      * Returned value will be an unencoded ``unicode`` string.