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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 hashmodel(model, library=None):
    '''Calculate the Hash id of metaclass ``meta``'''
    library = library or 'python-stdnet'
    meta = model._meta
    sha = hashlib.sha1(to_bytes('{0}({1})'.format(library, meta)))
    hash = sha.hexdigest()[:8]
    meta.hash = hash
    if hash in _model_dict:
        raise KeyError('Model "{0}" already in hash table.\
 Rename your model or the module containing the model.'.format(meta))
    _model_dict[hash] = model