在Django Admin中增加PositiveIntegerField的寬度

Question

在Django Admin中爲PositiveIntegerField增加輸入框寬度的正確方法是什麼？

UPDATE

這些都是我的文件：

models.py

from django.db import models 

class Report(models.Model): 
    datum  = models.DateField(unique=True, help_text='Od koji je datuma izvjestaj.') 
    osiguranika = models.PositiveIntegerField(help_text='Broj osiguranika.') 
    /* lot of staf below*/ 

    def __unicode__(self): 
     return str(self.datum) 

forms.py

from django import forms 
from hzmo_web.apps.hzmo.models import Report 

class ReportForm(forms.ModelForm): 
    class Meta: 
     model = Report 

    def __init__(self, *args, **kw): 
     super(ReportForm, self).__init__(*args, **kw) 
     self.fields['osiguranika'].widget.attrs['class'] = 'form-text' 

CSS

.form-text{ 
    width:750px; 
    height:250px; 
} 

Answer 1

models.py

class Num(models.Models): 
    number = models.PositiveIntegerField() 

forms.py

class NumForm(forms.ModelForm): 
    class Meta: 
     model = Num 

    def __init__(self, *args, **kw): 
     super(NumForm, self).__init__(*args, **kw) 
     self.fields['number'].widget.attrs['class'] = 'form-text' 

的style.css

.form-text{ 
    width:250px; 
     height:25px; 
} 

admin.py

class NumAdmin(AuditAdmin): 
    form = NumForm 
    list_display   = ('number',) 

    class Media: 
     css = { 
      'all': (/style.css',) 
     }