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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 search_by_prefix(portal_type, prefix):
 """Returns brains which share the same portal_type and ID prefix """

    catalog = api.get_tool("uid_catalog")
    brains = catalog({"portal_type": portal_type})
    # Filter brains with the same ID prefix
    return filter(lambda brain: api.get_id(brain).startswith(prefix), brains)