When reading source code of Django, I find some statements: 

class Field(object):  
    """Base class for all field types"""  
    __metaclass__ = LegacyConnection  

    # Generic field type description, usually overriden by subclasses
    def _description(self):
        return _(u'Field of type: %(field_type)s') % {
            'field_type': self.__class__.__name__
        }    
    description = property(_description) 

class AutoField(Field):
    description = _("Integer")

I know it set description as 'Integer', but don't understand the syntax: description = _("Integer").
Can some one help on it?

python django syntax
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