new_contents: import urllib
  import zipfile
  from geofunctions import *
  
  baseurl = 'http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/South_America/{0}{1:02}{2}{3:03}.hgt.zip'
  
  def demtilefromlonlat(coords):
      xi, yi = coords.astype(int)
      xstring = 'E' if xi > 0 else 'W'
      ystring = 'N' if yi > 0 else 'S'
      filename = tileformat.format(ystring, abs(yi), xstring, abs(xi))
      urllib.urlretrieve(baseurl+filename, cache_path+filename)
  
  
  coords = numpy.array(coordfromstring('-30, -50'))
  
  demtilefromlonlat(coords)
  
  
  
  dss = "http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/South_America/
  
subject: Create SrtmSources.py