value=[]

for i in range(0, 10):
    nit = mydataset_df.CO_tin_no
    url = 'http://www.rues.org.co/RM/ConsultaNIT_json'

    headers, payload = {
            'Content-Type':
            'application/x-www-form-urlencoded; charset=UTF-8'
        }, {'txtNIT': nit}
    r = requests.post(url, headers=headers, data=payload, timeout=4)
    if r.json().get('rows', False):
        res = r.json()['rows'][0]
        legal_name = res['razon_social'].title()
        value.append(legal_name)
        print value
        #mydataset_df['legal_name'] = value
    else:
        legal_name = 'no existe el numero %s' %nit
        value.append(legal_name)
        print value
        #mydataset_df['legal_name'] = value
   # print (row["name"], row["age"])

[u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']
[u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto', u'Pardo Jose Gilberto']