def to_case(argument, lower = False, swap = False, title = False, upper = False):
ret = []
last_item = ' '
for item in argument:
if type(item) == str:
if lower:
ret.append(item.lower())
elif swap:
ret.append(item.swapcase())
elif title:
ret.append(item.lower() if type(last_item) == str and last_item in str_upper + str_lower else item.upper())
elif upper:
ret.append(item.upper())
else:
ret.append(item)
last_item = item
return ret