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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 _parse_source_interface(self, config):
 """ Parses the conf block and returns the vxlan source-interface value Parses the provided configuration block and returns the value of vxlan source-interface. If the value is not configured, this method will return DEFAULT_SRC_INTF instead. Args: config (str):
 The Vxlan config block to scan Return: dict: A dict object intended to be merged into the resource dict """

        match = re.search(r'vxlan source-interface ([^\s]+)', config)
        value = match.group(1) if match else self.DEFAULT_SRC_INTF
        return dict(source_interface=value)