Write a simple parser that will parse and run Deadfish.  
Deadfish has 4 commands, each 1 character long:
* `i` increments the value (initially `0`)
* `d` decrements the value
* `s` squares the value
* `o` outputs the value into the return array
Invalid characters should be ignored.
```python
parse("iiisdoso")  ==>  [8, 64]
```
def parse(data):
    result = []
    value = 0
    for command in data:
        if command == 'i':
            value += 1
        elif command == 'd':
            value -= 1
        elif command == 's':
            value = value**2
        elif command == 'o':
            result.append(value)
    return result
def parse(data):
    result = []
    value = 0
    for command in data:
        if command == 'i':
            value += 1
        elif command == 'd':
            value -= 1
        elif command == 's':
            value = value**2
        elif command == 'o':
            result.append(value)
    return result