syntax error： invalid syntax 问题

[bolv6666]

各位大神，小弟初学python，下载数据的时候，运行.py文件总是出现这个错误，

download.py文件已经是在s:\Python_FNL文件夹下，且没有在python环境中，是在cmd环境中。download.py文件如下：

:: python script to download selected files from rda.ucar.edu
::
import sys
import os
import urllib2
import cookielib
::
if (len(sys.argv) != 2):
  print "usage: "+sys.argv[0]+" [-q] password_on_RDA_webserver"
  print "-q suppresses the progress message for each file that is downloaded"
  sys.exit(1)
::
passwd_idx=1
verbose=True
if (len(sys.argv) == 3 and sys.argv[1] == "-q"):
  passwd_idx=2
  verbose=False
::
cj=cookielib.MozillaCookieJar()
opener=urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
::
:: check for existing cookies file and authenticate if necessary
do_authentication=False
if (os.path.isfile("auth.rda.ucar.edu")):
  cj.load("auth.rda.ucar.edu",False,True)
  for cookie in cj:
    if (cookie.name == "sess" and cookie.is_expired()):
      do_authentication=True
else:
  do_authentication=True
if (do_authentication):
  login=opener.open("https://rda.ucar.edu/cgi-bin/login","email=[e-mail]&password="+sys.argv[1]+"&action=login")
::
:: save the authentication cookies for future downloads
:: NOTE! - cookies are saved for future sessions because overly-frequent authentication to our server can cause your data access to be blocked
  cj.clear_session_cookies()
  cj.save("auth.rda.ucar.edu",True,True)
::
:: download the data file(s)
listoffiles=["grib2/2017/2017.06/fnl_20170602_00_00.grib2","grib2/2017/2017.06/fnl_20170602_06_00.grib2","grib2/2017/2017.06/fnl_20170602_12_00.grib2"]
for file in listoffiles:
  idx=file.rfind("/")
  if (idx > 0):
    ofile=file[idx+1:]
  else:
    ofile=file
  if (verbose):
    sys.stdout.write("downloading "+ofile+"...")
    sys.stdout.flush()
  infile=opener.open("http://rda.ucar.edu/data/ds083.2/"+file)
  outfile=open(ofile,"wb")
  outfile.write(infile.read())
  outfile.close()
  if (verbose):
    sys.stdout.write("done.\n")

请问这是怎么回事呢

[bolv6666]

忘了说明，python 版本号3.7.4

[铖邑]

这个“::”应该是注释符“#”，你这样把注释部分全都当作代码执行了

[python全栈开发社区]

把：：换成 #

[一笑程序猴]

应该把所有的：：换成#