Get RA, Dec from an object name using the CDS Sesame web service in Python.

Sesame.py

import urllib
# source is a variable containing a source name, such as M31, Alpha Centauri, Sag A*, etc
source = "Sag A*"
# This is the string with the URL to query the Sesame service, 
# using a 'name' parameter.
# sesameQueryUrl = 'http://cdsws.u-strasbg.fr/axis/services/Sesame?'  +\
#                  'method=sesame&resultType=p&all=true&service=NSVA' +\
#                  '&name=%(name)s'
# use the updated CDS REST endpoint
sesameQueryUrl = 'http://cdsweb.u-strasbg.fr/cgi-bin/nph-sesame/-op/NSV?%(name)s'
# Build the query from the sesameQueryUrl and the dictionary
# We have to use urllib.quote to make it safe to include in a URL
sesameQuery = sesameQueryUrl % {
    'name': urllib.quote(source)
}

# Read the lines of the response from the final URL
sesameResponse = urllib.urlopen(sesameQuery).readlines()

# Parse the sesameResponse to get RA, Dec 
# oneliner: ra, dec = filter(lambda x: x.find('%J') == 0, sesameResponse)[0].split(' ')[1:3]
# The coordinates are in the lines starting with %J
coordinateList = filter(lambda x: x.find('%J') == 0, sesameResponse)
# As filter returns a list, get the first line
coordinates = coordinateList[0]
# Split the coordinates between the spaces, and drop de first item (%J) (so, start from the second on)
coordinates = coordinates.split(' ')[1:]
ra  = coordinates[0]
dec = coordinates[1]

print ra, dec