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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 unseal():
    '''
    Unseal Vault server

    This function uses the 'keys' from the 'vault' configuration to unseal vault server

    vault:
      keys:
        - n63/TbrQuL3xaIW7ZZpuXj/tIfnK1/MbVxO4vT3wYD2A
        - S9OwCvMRhErEA4NVVELYBs6w/Me6+urgUr24xGK44Uy3
        - F1j4b7JKq850NS6Kboiy5laJ0xY8dWJvB3fcwA+SraYl
        - 1cYtvjKJNDVam9c7HNqJUfINk4PYyAXIpjkpN/sIuzPv
        - 3pPK5X6vGtwLhNOFv1U2elahECz3HpRUfNXJFYLw6lid

    .. note: This function will send unsealed keys until the api returns back
             that the vault has been unsealed

    CLI Examples:

    .. code-block:: bash

        salt-run vault.unseal
    '''
    for key in __opts__['vault']['keys']:
        ret = __utils__['vault.make_request']('PUT', 'v1/sys/unseal', data=json.dumps({'key': key})).json()
        if ret['sealed'] is False:
            return True
    return False