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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(self, line):
 """ Find first occurrence of 'line' in file. This searches each line as a whole, if you want to see if a substring is in a line, use .grep() or .egrep() If found, return the line; this makes it easier to chain methods. :param line: String; whole line to find. :return: String or False. """

        if not isinstance(line, str):
            raise TypeError("Parameter 'line' not a 'string', is {0}".format(type(line)))
        if line in self.contents:
            return line
        return False