def findfile(item, fdir, match=False):
    """
    Find the file you need in a directory.
    Regular Expression is supported.
    """
    import os
    import re
    rs = []
    for i, j, k in os.walk(fdir):
        for na in k:
            if match == True:
                regitem = re.compile(item)
                d = re.match(regitem, na)
                if d is not None:
                    rs.append(os.path.join(i, na))
            else:
                regitem = re.compile(item)
                d = re.search(regitem, na)
                if d is not None:
                    rs.append(os.path.join(i, na))
    if rs == []:
        print("Can't find anything!")
    return rs
