```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>Digesti-Gastroi@23:52:29</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>2</hlevel>
            <item_name>Digestive system</item_name>
            <item_key>\\i2b2_DIAG\i2b2\Diagnoses\Digestive system (520-579)\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>Diagnoses \ Digestive system</tooltip>
            <class>ENC</class>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
    <panel>
        <panel_number>2</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>2</hlevel>
            <item_name>Gastrointestinal agents</item_name>
            <item_key>\\i2b2_MEDS\i2b2\Medications\MUL\(LME136) gastrointestinal agents\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>medications \ gastrointestinal agents</tooltip>
            <class>ENC</class>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
</ns4:query_definition>

```

I want to find diagnoses related to the digestive system (codes 520-579) and medications related to gastrointestinal agents (LME136) within the i2b2 database, with any timing and a specificity scale of 0, accuracy scale of 100, and no inversion. The query should include two panels, one for the digestive system diagnoses and another for gastrointestinal medications. The panels will have a total of one item occurrence each, and the class will be ENC (encounter).