rdflib query sparql cause parsing error with FILTER key

Question

I'm trying to run a SPARQL query against a graph with rdflib. It works well if i didn't use FILTER else it cause error on parsing the string to a query. i'm using PYTHON 2.7. Looking at other people query i cannot see any syntax error. Here the query:

 query = " SELECT ?textspan WHERE " \
             " { ?textspan rst:startOffset ?start ; " \
             "                    rst:endOffset ?end . " \
             "    FILTER ( ?start <= "+denotedStartOffset+" < ?end ) } " 

they same with:

 query = " SELECT ?textspan WHERE " \
             " { ?textspan rst:startOffset ?start ; " \
             "                    rst:endOffset ?end . " \
             "    FILTER ( ?start <= 5 < ?end ) } " 

The error:

Traceback (most recent call last):
  File "link.py", line 27, in <module>
    qres = g.query(QUERY_2)
  File "/usr/local/lib/python2.7/dist-packages/rdflib/graph.py", line 1085, in query
    query_object, initBindings, initNs, **kwargs))
  File "/usr/local/lib/python2.7/dist-packages/rdflib/plugins/sparql/processor.py", line 74, in query
    parsetree = parseQuery(strOrQuery)
  File "/usr/local/lib/python2.7/dist-packages/rdflib/plugins/sparql/parser.py", line 1058, in parseQuery
    return Query.parseString(q, parseAll=True)
  File "/usr/local/lib/python2.7/dist-packages/pyparsing.py", line 1947, in parseString
    raise exc
pyparsing.ParseException: Expected {SelectQuery | ConstructQuery | DescribeQuery | AskQuery}, found u'F'  (at char 103), (line:1, col:104)

It says it doesn't expect 'F' so it doesn't recognize FILTER.

Answer 1

As @UninformedUser suggest the solution was FILTER ( ?start <= 5 && 5 < ?end )