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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def detectAllKws(self):
 """ Detect all keyword from infile, return as a list USAGE: kwslist = detectAllKws() """

        kwslist = []
        for line in self.file_lines:
            # if line.strip() == '': continue
            line = ''.join(line.strip().split())
            if line.startswith("!"):
                continue
            # if ':' in line and not "line" in line:
            if ':' in line:
                kw_name = line.split(':')[0]
                if set(kw_name).difference({'=', '-', '*', '/', '+'}) == set(kw_name):
                    kwslist.append(kw_name)
        return kwslist