def __init__(self, parent, dataset, variables=False):
QtGui.QComboBox.__init__(self, parent)<EOL>self.identifiers = []<EOL>self.columns = dataset.get_column_names(virtual=True)<EOL>self.identifiers.extend(vaex.dataset.expression_namespace.keys())<EOL>self.identifiers.extend(self.columns)<EOL>if variables:<EOL><INDENT>self.identifiers.extend(list(dataset.variables.keys()))<EOL><DEDENT>self.addItems(["<STR_LIT>"] + self.columns)<EOL>self.setEditable(True)<EOL>lineEdit = self.lineEdit()<EOL>self.completer = IdentifierCompleter(lineEdit, self.identifiers)<EOL>lineEdit.setCompleter(self.completer)<EOL>
:param parent:
:param Dataset dataset: