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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_table(table):
 """ Ensure the table is valid for converting to grid table. * The table must a list of lists * Each row must contain the same number of columns * The table must not be empty Parameters table : list of lists of str The list of rows of strings to convert to a grid table Returns ------- message : str If no problems are found, this message is empty, otherwise it tries to describe the problem that was found. """

    if not type(table) is list:
        return "Table must be a list of lists"

    if len(table) == 0:
        return "Table must contain at least one row and one column"

    for i in range(len(table)):
        if not type(table[i]) is list:
            return "Table must be a list of lists"
        if not len(table[i]) == len(table[0]):
            "Each row must have the same number of columns"

    return ""