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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 convert_meta(self):
 """ Parses the meta_str to python dictionary and stores in ``meta`` attribute. """

        if self.meta_str:
            self.meta_str = regex_meta.findall(self.meta_str + ',')
        if self.meta_str:
            for par in self.meta_str:
                if par[0] is not '':
                    val1 = par[0]
                    val2 = par[1]
                else:
                    val1 = par[2]
                    val2 = par[3]
                val1 = val1.strip()
                val2 = val2.strip()
                if val1 in CRTFParser.valid_global_keys or val1 == 'label':
                    if val1 in ('range', 'corr', 'labeloff'):
                        val2 = val2.split(',')
                        val2 = [x.strip() for x in val2]
                    self.meta[val1] = val2
                else:
                    self._raise_error("'{0}' is not a valid meta key".format(val1))

        self.meta['include'] = self.include != '-'
        self.include = self.meta['include']

        if 'range' in self.meta:
            self.meta['range'] = [u.Quantity(x) for x in self.meta['range']]

        self.meta['type'] = self.type_