Parsing Twitter Handles | Python Fiddle

def all_letters(value):
    """

:type value: str
    :rtype: bool
    """
    for v in value.lower():
        if v not in "abcdefghijklmnopqrstuvwxyz":
            return False
    return True

def all_numbers(value):
    """

:type value: str
    :rtype: bool
    """
    for v in value.lower():
        if v not in "1234567890":
            return False
    return True

def has_mixed_case(value):
    """

:type value: str
    :rtype: bool
    """
    has_upper = False
    has_lower = False
    for v in value.lower():
        if v in "abcdefghijklmnopqrstuvwxyz":
            has_lower = True
            break
    if not has_lower:
        return False
    for v in value.upper():
        if v in "abcdefghijklmnopqrstuvwxyz":
            has_upper = True
            break
    return has_upper and has_lower

def split_on_case_two(value):
    value_with_commas = ""
    for index, char in enumerate(value):
        try:
            upper = char.upper()
            next_upper = value[index + 1].upper()
            if char == upper and value[index + 1] != next_upper:
                value_with_commas += "," + char
                continue
            if char == char.lower() and value[index + 1] != value[index + 1].lower():
                value_with_commas += char + ","
                continue
        except IndexError:
            pass

value_with_commas += char
    return value_with_commas.replace(",,", ",").strip(",").split(",")

def likely_structure(value):
    """

:type value:str
    :rtype:str
    """
    # parts are : word, letter, number
    parts = []

if "_" in value:
        splits = value.split("_")
    else:
        splits = split_on_case_two(value)

# split on dictionary word? split on common names?

for part in splits:
        # check if name, if english word
        if all_letters(part) and part != part.upper():
            parts.append("WORD")
        elif len(part) > 1 and all_letters(part) and part == part.upper():
            # Not really, but hey.
            parts.append("ACRONYM")
        elif len(part) == 1 and all_letters(part) and part == part.upper():
            parts.append("INITIAL")
        elif all_letters(part):
            parts.append("NUMBER" + str(len(part)))
        elif len(part) > 1 and part[0].isalpha() and part[-1].isnumeric():
            parts.append("STRNUMBER")
        elif part.isnumeric():
            parts.append("NUMBER")
        else:
            parts.append("STRING")
    return parts

for value in ["MisterSql", "MisterSQL", "MisterSQLMan",
              "MisterEsQueEll", "mistersql", "MRSQL",
              "M1R2S3Q4L", "12341234", "Mister_SQL", "MISTER_S_Q_L", "Mister_SQL_Man",
              "Mister_Es_Que_El"]:
    print(value + "  " + str(likely_structure(value)))

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