------
## 最终结论
```python
def check_occurences(tuples_list):
    from collections import defaultdict
    
    occurrences = defaultdict(int)
    
    for a, b in tuples_list:
        # Sort the tuple to handle unordered pairs
        key = tuple(sorted((a, b)))
        occurrences[key] += 1
    
    return dict(occurrences)

# Test cases
assert check_occurences([(3, 1), (1, 3), (2, 5), (5, 2), (6, 3)]) == {(1, 3): 2, (2, 5): 2, (3, 6): 1}
assert check_occurences([(4, 2), (2, 4), (3, 6), (6, 3), (7, 4)]) == {(2, 4): 2, (3, 6): 2, (4, 7): 1}
assert check_occurences([(13, 2), (11, 23), (12, 25), (25, 12), (16, 23)]) == {(2, 13): 1, (11, 23): 1, (12, 25): 2, (16, 23): 1}
```