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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(pattern, filename):
 """Very simple grep that returns the first matching line in a file. String matching only, does not do REs as currently implemented. """

    try:
        # for line in file
        # if line matches pattern:
        #    return line
        return next((L for L in open(filename) if L.find(pattern) >= 0))
    except StopIteration:
        return ''