How to query a key that has ":" in the dictionary
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### Summary
Suppose I have my data as below
```
{
    "col1" : "firstcolumn",
    "col2" : "secondcolumn",
    "col3" : {
	 "abc:text" : "environment",
	 "cde"      : "hello"
    }
}
```

Now if I want to filter the rows that has **cde** as key and  value **hello**, I can use the below query
```
query{
    table(filter : {col3 : {contains : {cde : "hello"}}}){
	nodes{
	    col2,
	    col1
	}
    }
}
```

How to query if I want to get the rows where the key is having a **colon** (:) in it? 
Ex: How to query if I need to get the rows that has **abc:text** as key and value is **environment**?
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