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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 check_block(block_id):
 """ Verify that a block ID is valid True False False False False True """

    if type(block_id) not in [int, long]:
        return False

    if BLOCKSTACK_TEST:
        if block_id <= 0:
            return False

    else:
        if block_id < FIRST_BLOCK_MAINNET:
            return False

    if block_id > 1e7:
        # 1 million blocks? not in my lifetime
        return False

    return True