===== ISTEM =====
Solve the following programming task.

TASK: Valid Parentheses

Write a function 'is_valid_parentheses(s)' that takes a string containing only the characters '(', ')', '{', '}', '[' and ']'. Every opening bracket must be closed by the same type of bracket in the correct order. An empty string is considered valid.

STARTER CODE (python):
def is_valid_parentheses(s: str) -> bool:
    # Write your code here
    pass


RULES:
- Keep the function name and signature EXACTLY as given.
- Return working code only. No explanations.
- Put the code in a single ``` block.
- Try to solve it first. If you genuinely cannot, write only this single
  line instead of producing faulty code: CANNOT_SOLVE

===== HAM YANIT =====
```python
def is_valid_parentheses(s: str) -> bool:
    stack = []
    mapping = {')': '(', ']': '[', '}': '{'}
    for char in s:
        if char in '([{':
            stack.append(char)
        elif char in mapping:
            if not stack or stack.pop() != mapping[char]:
                return False
        else:
            # ignore other characters (though per problem statement, only brackets appear)
            return False
    return not stack
```
