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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 collect_files(dirpath, cond=lambda fullname: True):
 """ Recursively collect the files contained inside dirpath. :param dirpath: path to a readable directory :param cond: condition on the path to collect the file """

    files = []
    for fname in os.listdir(dirpath):
        fullname = os.path.join(dirpath, fname)
        if os.path.isdir(fullname):  # navigate inside
            files.extend(collect_files(fullname))
        else:  # collect files
            if cond(fullname):
                files.append(fullname)
    return files