args in: {file_name, type = 'file_type', delete = [], start = [], end = [], both = [], lower_case = Bool}

file_name: Name of the file with extension as string
path   : only specify if the file is in a different directory, input as string
type   : 'txt' or 'pdf'
delete : Removes the char everywhere in the string_list
start  : Removes the char at the start of string_list but not everywhere
end    : Removes the char at the end of string_list but not everywhere
both   : Removes the char at either ends. If both is defined, start and end lists are redundant
lower_case: Boolean input for forcing all chars to lower case; True by default