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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 CacheObject(self, identifier, vfs_object):
 """Caches a VFS object. This method ignores the cache value reference count. Args: identifier (str):
 VFS object identifier. vfs_object (object):
 VFS object to cache. Raises: CacheFullError: if he maximum number of cached values is reached. KeyError: if the VFS object already is cached. """

    if identifier in self._values:
      raise KeyError('Object already cached for identifier: {0:s}'.format(
          identifier))

    if len(self._values) == self._maximum_number_of_cached_values:
      raise errors.CacheFullError('Maximum number of cached values reached.')

    self._values[identifier] = ObjectsCacheValue(vfs_object)