The function seems to shift each alphabetical character in the input string by 6 positions forward in the alphabet, maintaining the case of the character. For example, 'a' becomes 'g' and 'A' becomes 'G'. Numeric and non-alphabetic characters in the input are not affected.

[CODE]:

```python
def f(x):
    result = []
    for char in x:
        if char.isalpha():
            shift = 6
            shifted = chr(((ord(char.upper()) - ord('A') + shift) % 26) + ord('A'))
            if char.islower():
                result.append(shifted.lower())
            else:
                result.append(shifted)
        else:
            result.append(char)
    return "".join(result)
```