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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 is_line_in_file(filename: str, line: str) -> bool: """ Detects whether a line is present within a file. Args: filename: file to check line: line to search for (as an exact match) """

    assert "\n" not in line
    with open(filename, "r") as file:
        for fileline in file:
            if fileline == line:
                return True
        return False