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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 _set_from_ini(self, namespace, ini_file):
 """ Copy values from loaded INI file to namespace. """

        # Isolate global values
        global_vars = dict((key, val)
            for key, val in namespace.items()
            if isinstance(val, basestring)
        )

        # Copy all sections
        for section in ini_file.sections():
            # Get values set so far
            if section == "GLOBAL":
                raw_vars = global_vars
            else:
                raw_vars = namespace.setdefault(section.lower(), {})

            # Override with values set in this INI file
            raw_vars.update(dict(ini_file.items(section, raw=True)))

            # Interpolate and validate all values
            if section == "FORMATS":
                self._interpolation_escape(raw_vars)
            raw_vars.update(dict(
                (key, validate(key, val))
                for key, val in ini_file.items(section, vars=raw_vars)
            ))

        # Update global values
        namespace.update(global_vars)