```xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns4:query_definition xmlns:ns2="http://www.i2b2.org/xsd/cell/crc/psm/1.1/" xmlns:ns4="http://www.i2b2.org/xsd/cell/crc/psm/querydefinition/1.1/" xmlns:ns3="http://www.i2b2.org/xsd/cell/crc/psm/analysisdefinition/1.1/">
    <query_name>Patient Instruc@13:58:27</query_name>
    <query_timing>ANY</query_timing>
    <specificity_scale>0</specificity_scale>
    <panel>
        <panel_number>1</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>0</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>3</hlevel>
            <item_name>Analgesics</item_name>
            <item_key>\\i2b2_MEDS\i2b2\Medications\MUL\(LME92) central nervous system agents\(LME93) analgesics\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>medications \ central nervous system agents \ analgesics</tooltip>
            <class>ENC</class>
            <constrain_by_modifier>
                <modifier_name>Patient Instructions</modifier_name>
                <modifier_key>\\i2b2_MEDS\Medication\Instructions\</modifier_key>
                <applied_path>\i2b2\Medications\%</applied_path>
            </constrain_by_modifier>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
</ns4:query_definition>

```

I want to find all instances of medications related to analgesics in the central nervous system agents category, with any specificity scale and timing, and constrained by the "Patient Instructions" modifier applied to the medications path.