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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 strip_quotes(self, content):
 """ Unquote given rule. Args: content (str):
 An import rule. Raises: InvalidImportRule: Raise exception if the rule is badly quoted (not started or not ended quotes). Returns: string: The given rule unquoted. """

        error_msg = "Following rule is badly quoted: {}"
        if (content.startswith('"') and content.endswith('"')) or \
           (content.startswith("'") and content.endswith("'")):
            return content[1:-1]
        # Quote starting but not ended
        elif (content.startswith('"') and not content.endswith('"')) or \
             (content.startswith("'") and not content.endswith("'")):
            raise InvalidImportRule(error_msg.format(content))
        # Quote ending but not started
        elif (not content.startswith('"') and content.endswith('"')) or \
             (not content.startswith("'") and content.endswith("'")):
            raise InvalidImportRule(error_msg.format(content))

        return content