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| ? | The preceding item will be matched zero or one times | 
| * | The preceding item will be matched zero or more times | 
| + | The preceding item will be matched one or more times | 
| {n} | The preceding item will be matched exactly n times | 
| {n,} | The preceding item will be matched n or more times | 
| {n,m} | The preceding item will be matched from n to m times |