def build_project(project_name):
    """Builds eclipse project file.

    Uses a very simple template to generate an eclipse .project file
    with a configurable project name.

    Args:
        project_name: Name of the eclipse project. When importing the project
            into an eclipse workspace, this is the name that will be shown.
    Returns:
        Contents of the eclipse .project file.
    """
    template = """<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
    <name>{project_name}</name>
    <comment>
    </comment>
    <projects>
    </projects>
    <buildSpec>
        <buildCommand>
            <name>org.python.pydev.PyDevBuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
        <buildCommand>
            <name>org.eclipse.jdt.core.javabuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
    </buildSpec>
    <natures>
        <nature>org.eclipse.jdt.core.javanature</nature>
        <nature>org.python.pydev.pythonNature</nature>
    </natures>
</projectDescription>"""
    return template.format(project_name=project_name)