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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 _get_activate_script(cmd, venv):
 """Returns the string to activate a virtualenv. This is POSIX-only at the moment since the compat (pexpect-based) shell does not work elsewhere anyway. """

    # Suffix and source command for other shells.
    # Support for fish shell.
    if "fish" in cmd:
        suffix = ".fish"
        command = "source"
    # Support for csh shell.
    elif "csh" in cmd:
        suffix = ".csh"
        command = "source"
    else:
        suffix = ""
        command = "."
    # Escape any spaces located within the virtualenv path to allow
    # for proper activation.
    venv_location = str(venv).replace(" ", r"\ ")
    # The leading space can make history cleaner in some shells.
    return " {2} {0}/bin/activate{1}".format(venv_location, suffix, command)