def __init__(self, name='<STR_LIT>', defaultValue=irNull, encoding=None):
self.valueType = None<EOL>self.defaultValue = defaultValue<EOL>self.encoding = encoding<EOL>
__init__ - Create an IRBytesField object

@param name <str> - Field name

@param defaultValue <any> default irNull - Default value for this field

@param encoding <None/str> - If None, defaultIREncoding will be used when converting to bytes,
  otherwise you can provide an explicit encoding

An IRBytesField is indexable, and the index is forced to be hashed.