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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 grep(regex, output):
 """Similar to linux's `grep`, this returns the line in an output stream that matches a given regex pattern. It does not rely on the `grep` binary and is not sensitive to line endings, so it can be used cross-platform. Args: regex: string, a regex that matches the expected pattern. output: byte string, the raw output of the adb cmd. Returns: A list of strings, all of which are output lines that matches the regex pattern. """

    lines = output.decode('utf-8').strip().splitlines()
    results = []
    for line in lines:
        if re.search(regex, line):
            results.append(line.strip())
    return results