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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 getmtime(self, path=None, client_kwargs=None, header=None):
 """ Return the time of last access of path. Args: path (str):
 File path or URL. client_kwargs (dict):
 Client arguments. header (dict):
 Object header. Returns: float: The number of seconds since the epoch (see the time module). """

        return self._getmtime_from_header(
            self.head(path, client_kwargs, header))