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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 upload_entities(namespace, workspace, entity_data):
 """Upload entities from tab-delimited string. Args: namespace (str):
 project to which workspace belongs workspace (str):
 Workspace name entity_data (str):
 TSV string describing entites Swagger: https://api.firecloud.org/#!/Entities/importEntities """

    body = urlencode({"entities" : entity_data})
    headers = _fiss_agent_header({
        'Content-type':  "application/x-www-form-urlencoded"
    })
    uri = "workspaces/{0}/{1}/importEntities".format(namespace, workspace)
    return __post(uri, headers=headers, data=body)