Querying Contacts by Email in JSON Format

here is the query I am inputting { "type": "and", "queries": [ { "type": "object_type", "object_type": "contact" }, { "type": "field_condition", "field": { "type": "regular_field", "object_type": "contact", "field_name": "email" }, "condition": { "type": "text", "value": " " } } ] }