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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 get_hook(hook_name):
 """Returns the specified hook. Args: hook_name (str) Returns: str - (the content of) the hook Raises: HookNotFoundError """

    if not pkg_resources.resource_exists(__name__, hook_name):
        raise HookNotFoundError
    return pkg_resources.resource_string(__name__, hook_name)