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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 _metadata_keyword(self):

 """
 Define the most important tab parameters for a keyword-type tab file
 """

        with open(self.abspath) as fobj:
            for line in fobj:
                if 'PVTTABLE LABEL' in line:
                    label = re.findall(r"\=[\w\ \"]*\,", line)[0][1:-1]
                    self.metadata["fluids"].append(label)

                if 'PRESSURE = (' in line:
                    line = line.split('=')[1]
                    vals = re.findall(r'[\d\-\.eE+]+', line)
                    self.metadata['p_array'] = np.array([float(val) for val in
                                                         vals])
                if 'TEMPERATURE = (' in line:
                    line = line.split('=')[1]
                    vals = re.findall(r'[\d\-\.eE+]+', line)
                    self.metadata['t_array'] = np.array([float(val) for val in
                                                         vals])
                if 'COLUMNS = (' in line:
                    line = line.split('=')[1].replace(" ", "").\
                           replace('(', '').replace(')\n', '')
                    self.metadata['properties'] = line.split(',')
            self.metadata["t_points"] = len(self.metadata["t_array"])
            self.metadata["p_points"] = len(self.metadata["p_array"])
            self.metadata["nfluids"] = len(self.metadata["fluids"])
            self.data = pd.DataFrame(self.metadata["properties"])