code: function(labelStr) {
      labelStr = labelStr || ''
      if (String(process.env.NODE_ENV).toLowerCase() == 'development') {
        labelStr = labelStr.replace(/^(test_|)/i, 'test_')
      };
      var legal = cons.isAtomic(labelStr);
      // SQL injection scan here
      if (!legal) {
        throw new Error("individual label cannot contain space.")
      };
      return labelStr ? labelStr.toLowerCase().replace(/\s+/g, ' ') : ''
    }
docs: Format a Neo4j Label string into lower case, single spaced. Has SQL-injection prevention.
  If NODE_ENV is 'development', it prepends 'test_' to labelStr (if not already exists prepended).
  @private
  @param  {string} labelStr The label string
  @return {string}          formattedString
  
  @example
  cons.formatLabel('dis a COOL  label')
  // => 'this a cool label'