diff --git a/openlamb.py b/openlamb.py
index 59ecfe0..d74c391 100755
--- a/openlamb.py
+++ b/openlamb.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/python3
 
 import argparse
 import traceback
@@ -7,6 +7,7 @@ import pandas as pd
 import numpy as np
 from sodapy import Socrata
 import matplotlib.pyplot as plt
+import re
 import glob
 import os
 from os import getcwd, chdir
@@ -18,6 +19,21 @@ datasets_ambiente = {"2020": "nicp-bhqi",
                      "2018": "bgqm-yq56",
                      "2017": "j8j8-qsb2"}
 
+csv_ambiente = {"sensori_aria_1968-1995.zip": "puwt-3xxh",
+                "sensori_aria_1996-2000.zip": "wabv-jucw",
+                "sensori_aria_2001-2004.zip": "5jdj-7x8y",
+                "sensori_aria_2005-2007.zip": "h3i4-wm93",
+                "sensori_aria_2008-2010.zip": "wp2f-5nw6",
+                "sensori_aria_2011.zip": "5mut-i45n",
+                "sensori_aria_2012.zip": "wr4y-c9ti",
+                "sensori_aria_2013.zip": "hsdm-3yhd",
+                "sensori_aria_2014.zip": "69yc-isbh",
+                "sensori_aria_2015.zip": "bpin-c7k8",
+                "sensori_aria_2016.zip": "7v3n-37f3",
+                "sensori_aria_2017.zip": "fdv6-2rbs",
+                "sensori_aria_2018.zip": "4t9j-fd8z",
+                "sensori_aria_2019.zip": "j2mz-aium"}
+
 
 def _connect():
     client = Socrata("www.dati.lombardia.it", None)
@@ -99,6 +115,69 @@ def list_of_csv_files(dir_name):
     return filelist
 
 
+def parse_range(x):
+    x = x.strip()
+    if x.isdigit():
+        yield str(x)
+    elif '-' in x:
+        xr = x.split('-')
+        yield from range(int(xr[0].strip()), int(xr[1].strip()) + 1)
+    else:
+        raise ValueError(f"Unknown range specified: {x}")
+
+
+def get_csv_dict(dict):
+    d = {}
+    for (k, v) in dict.items():
+        filename, id = k, v
+        match_multi = re.search("\\d{4}-\\d{4}", filename)
+        match_single = re.search("\\d{4}", filename)
+        if match_multi:
+            years = [str(x) for x in parse_range(str(match_multi.group()))]
+        elif match_single:
+            years = [match_single.group()]
+        else:
+            print("no match")
+        for year in years:
+            d.update({year: [filename, id]})
+    return d
+
+
+def check_csv(args, filelist, csv_dict):
+    years = [str(x) for x in parse_range(args)]
+    f = []
+    for y in years:
+        if y not in csv_dict.keys():
+            print("Errore: i dati per l'anno %s non sono disponibili come csv" % y)
+            sys.exit(-1)
+        if csv_dict[y][0] not in filelist:
+            print("file %s for year %s is not available in folder %s" % (csv_dict[y][0], y, path_to_csv_files))
+            download_csv(csv_dict[y][0], csv_dict[y][1], path_to_csv_files)
+        f.append(csv_dict[y][0])
+    return f
+
+
+def download_csv(filename, id, path):
+    print("downloading %s....... please wait" % filename)
+    import requests
+    url = "https://www.dati.lombardia.it/download/" + id + "/application%2Fzip"
+    req = requests.get(url, allow_redirects=True)
+    try:
+        req.raise_for_status()
+    except (requests.ConnectionError,
+            requests.RequestException,
+            requests.HTTPError,
+            requests.Timeout,
+            requests.TooManyRedirects) as e:
+        print("Download error: \n\t %s" % str(e))
+        sys.exit(-1)
+    else:
+        f = open(os.path.dirname(path) + "/" + filename, "wb")
+        f.write(req.content)
+        f.close()
+        pass
+
+
 def main():
     parser = argparse.ArgumentParser()
     parser.add_argument("--dataset", nargs='+', required=False,
@@ -110,19 +189,16 @@ def main():
     args = parser.parse_args()
 
     try:
-        dati_csv = []
+        csv_dict = get_csv_dict(csv_ambiente)
         csv_files = list_of_csv_files(path_to_csv_files)
+        dati_csv = []
         if args.csv:
-            if "all" in args.csv:
-                dati_csv = csv_files
+            if not re.search("\\d{4}-\\d{4}", args.csv[0]):
+                if not re.search("\\d{4}", args.csv[0]):
+                    print("Error: syntax for --csv parameter:  year for single year or year1-year2 for years range")
             else:
-                for d in args.csv:
-                    if d in csv_files:
-                        dati_csv.append(d)
-                    else:
-                        print("spiacente, ma il file csv %s non e' disponibile nel "
-                              "percorso indicato:  %s" % (d, path_to_csv_files))
-                        sys.exit(-1)
+                dati_csv = check_csv(args.csv[0], csv_files, csv_dict)
+                print("daty csv = %s" % dati_csv)
         dati = []
         if args.dataset:
             if "all" in args.dataset:
@@ -132,7 +208,8 @@ def main():
                 for d in args.dataset:
                     dati.append(datasets_ambiente[d])
         dataframes = get_dataframes(dati_csv, dati, args.sensori)
-        datamerged = merge_df(dataframes, dataframes.keys())
+        datamerged = merge_df(dataframes, list(dataframes.keys()))
+        datamerged.to_csv("export.csv")
         import stazioni
         s = stazioni.get_stazioni()
         for sensore in datamerged.columns[1:]: