```python
def correct_bracketing(brackets: str):
    """ brackets is a string of "(" and ")".
    return True if every opening bracket has a corresponding closing bracket.

    >>> correct_bracketing("(")
    False
    >>> correct_bracketing("()")
    True
    >>> correct_bracketing("(()())")
    True
    >>> correct_bracketing(")(()")
    False
    """
    depth = 0
    for char in brackets:
        if char == '(':
            depth += 1
        elif char == ')':
            depth -= 1
            if depth < 0:
                return False
    return depth == 0
```