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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 execute_only_once():
 """ Each called in the code to this function is guaranteed to return True the first time and False afterwards. Returns: bool: whether this is the first time this function gets called from this line of code. Example: .. code-block:: python if execute_only_once():
 # do something only once """

    f = inspect.currentframe().f_back
    ident = (f.f_code.co_filename, f.f_lineno)
    if ident in _EXECUTE_HISTORY:
        return False
    _EXECUTE_HISTORY.add(ident)
    return True