import urllib2


url = 'http://www.rcsb.org/pdb/rest/search'

queryText = """

<?xml version="1.0" encoding="UTF-8"?>
<orgPdbCompositeQuery version="1.0">
  <queryRefinement>
    <queryRefinementLevel>0</queryRefinementLevel>
    <orgPdbQuery>
      <version>head</version>
      <queryType>org.pdb.query.simple.EnzymeClassificationQuery</queryType>
      <description>Enzyme Classification Search : EC=6.1.1.*</description>
      <Enzyme_Classification>6.1.1.*</Enzyme_Classification>
    </orgPdbQuery>
  </queryRefinement>
  <queryRefinement>
    <queryRefinementLevel>1</queryRefinementLevel>
    <conjunctionType>and</conjunctionType>
    <orgPdbQuery>
      <version>head</version>
    <queryType>org.pdb.query.simple.ExpTypeQuery</queryType>
    <description>Experimental Method is X-RAY</description>
    <mvStructure.expMethod.value>X-RAY</mvStructure.expMethod.value>
  </orgPdbQuery>
 </queryRefinement>
</orgPdbCompositeQuery>"
"""

print "query:\n", queryText

print "querying PDB...\n"

req = urllib2.Request(url, data=queryText)

f = urllib2.urlopen(req)

result = f.read()


if result:

    print "Found number of PDB entries:", result.count('\n')

else:

    print "Failed to retrieve results"