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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 to_envvars(self):
 """ Export property values to a dictionary with environment variable names as keys. """

        export = {}
        for prop_name in self.profile_properties:
            prop = self._get_prop(prop_name)
            value = self[prop_name]
            if value is not None:
                export[prop.get_envvar(self)] = prop.to_str(self, value)
        if self._profile_parent_name:
            export[
                f"{self._envvar_prefix}PARENT_PROFILE".upper()
            ] = self._profile_parent_name
        return export