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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 _removeHeaderTag(header, tag):
 """Removes a tag from the beginning of a header string. :param header: str :param tag: str :returns: (str, bool), header without the tag and a bool that indicates wheter the tag was present. """

    if header.startswith(tag):
        tagPresent = True
        header = header[len(tag):]
    else:
        tagPresent = False
    return header, tagPresent