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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 hash(value):
    '''Detect an hash type'''
    if not value:
        return
    elif len(value) == 32:
        type = 'md5'
    elif len(value) == 40:
        type = 'sha1'
    elif len(value) == 64:
        type = 'sha256'
    else:
        return None
    return {'type': type, 'value': value}