def isMatch(peak, biomarker, tolerance):
    """Check if spectral peak matches protein biomarker

    Args:
        peak: Spectral peak obatained from experiment, float
        biomarker: An array of biomarker values
        tolerance: Maximal difference between experimental weight and
        theoretical one that could be considered a match. float

    Return:
        True / False
    """

    for each in biomarker:
        if abs(float(peak) - each) <= float(tolerance):
            return True
    return False