def nameToLabel(mname):
    """
    Convert a string like a variable name into a slightly more human-friendly
    string with spaces and capitalized letters.

    @type mname: C{str}
    @param mname: The name to convert to a label.  This must be a string
    which could be used as a Python identifier.  Strings which do not take
    this form will result in unpredictable behavior.

    @rtype: C{str}
    """
    labelList = []
    word = ''
    lastWasUpper = False
    for letter in mname:
        if letter.isupper() == lastWasUpper:
            # Continuing a word.
            word += letter
        else:
            # breaking a word OR beginning a word
            if lastWasUpper:
                # could be either
                if len(word) == 1:
                    # keep going
                    word += letter
                else:
                    # acronym
                    # we're processing the lowercase letter after the acronym-then-capital
                    lastWord = word[:-1]
                    firstLetter = word[-1]
                    labelList.append(lastWord)
                    word = firstLetter + letter
            else:
                # definitely breaking: lower to upper
                labelList.append(word)
                word = letter
        lastWasUpper = letter.isupper()
    if labelList:
        labelList[0] = labelList[0].capitalize()
    else:
        return mname.capitalize()
    labelList.append(word)
    return ' '.join(labelList)

    Convert a string like a variable name into a slightly more human-friendly
    string with spaces and capitalized letters.

    @type mname: C{str}
    @param mname: The name to convert to a label.  This must be a string
    which could be used as a Python identifier.  Strings which do not take
    this form will result in unpredictable behavior.

    @rtype: C{str}
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/util.py